As the world’s population ages, the number of people living with dementias such as Alzheimer’s disease increases. Given the lack of curative treatments and the limited effectiveness of available medications, interest in new therapeutic approaches is growing. Among them are cannabinoids from the cannabis plant.
A small new Brazilian study published in the international Journal of Alzheimer’s Disease investigated the effects of microdoses of cannabis extract on patients with mild Alzheimer’s disease. The results found positive effects, without the associated “high” of cannabis.
The logic of microdoses
The study, led by professor Francisney Nascimento and colleagues at the Federal University of Latin American Integration (UNILA), recruited 24 elderly patients (60-80 years) diagnosed with mild Alzheimer’s. It evaluated the effects of daily use of an oil prepared from Cannabis extract containing THC and CBD in similar proportions and extremely low concentrations (0.3 mg of each cannabinoid). These sub-psychoactive doses do not cause the “high” associated with recreational use of the plant.
The extract used was donated by ABRACE, Brazil’s biggest patient association and had no contribution from cannabis companies or other funding sources.
“Microdosing” is a term usually associated with recreational use of psychedelics. Given the size of the dose, it would be easy to question whether it could have any effect at all.
Doses below 1 mg of the cannabinoid compounds are not frequently reported in the literature of clinical practice. However, the researchers’ decision to use microdosing did not come out of nowhere. In 2017, the group led by Andreas Zimmer and Andras Bilkei-Gorzo had already demonstrated that very low doses of THC restored cognition in elderly mice, reversing gene expression patterns and brain synapse density in the hippocampus to levels similar to those of young animals.
Subsequently, other studies in mice reinforced that the endocannabinoid system, which is important for neuroprotection and regulates normal brain activity (ranging from body temperature to memory), undergoes a natural decline during ageing.
Inspired by these findings, the group initially tested microdosing of cannabis extract in a single patient with Alzheimer’s disease for 22 months. They found cognitive improvement, assessed using the Adas-Cog scale, a set of tasks using things like word recall to test cognitive function. This triggered the decision to run a more robust clinical trial in human volunteers to verify the cognitive-enhancement effects observed in the volunteer. The second study was a properly controlled randomised and double-blinded clinical trial.
What we found
Several clinical scales were used to objectively measure the impact of cannabis treatment. This time, the improvement was observed in the mini-mental state exam (MMSE) scale, a widely used scale for assessing cognitive function in patients with dementia. It’s a validated set of questions that are asked to the patient, with the aid of an accompanying person (typically a family member of helper). After 24 weeks of treatment, the group receiving the cannabis extract showed stabilisation in their scores, while the placebo group showed cognitive deterioration (worsening of Alzheimer’s symptoms).
The impact was modest but relevant, patients using cannabis microdosing scored two to three points higher than their placebo counterparts (full points on the MMSE is 30). In patients with preserved or moderately impaired cognitive function, it may be unrealistic to expect major changes in a few weeks.
Cannabis extracts did not improve other non-cognitive symptoms, like depression, general health or overall quality of life. On the other hand, there was no difference in adverse side effects. This was likely due to the extremely low dose used.
This result echoes findings from my 2022 study which found a reduction in endocannabinoid signalling during ageing, meaning ageing brains are more prone to cognitive degradation without the protection of the cannabinoids. Among other mechanisms, cannabinoids seem to protect cognition by reducing drivers of inflammation in the brain.
A new paradigm: cannabis without the ‘high’
The biggest obstacle to the acceptance of cannabis as a therapeutic tool in brain ageing is perhaps not scientific, but cultural. In many countries, the fear of “getting high” deters many patients and even healthcare professionals. But studies such as this show there are ways to get around this problem by using doses so low they do not cause noticeable changes in consciousness, but which can still modulate important biological systems, such as inflammation and neuroplasticity.
Microdoses of cannabis can escape the psychoactive zone and still deliver benefits. This could open the door to new formulations focused on prevention, especially in more vulnerable populations, such as elderly people with mild cognitive impairment or a family history of dementia.
What now?
Despite its potential, the study also has important limitations: the sample size is small, and the effects were restricted to one dimension of the cognition scale. Still, the work represents an unprecedented step: it is the first clinical trial to successfully test the microdose approach in patients with Alzheimer’s disease. It is a new way of looking at this plant in the treatment of important diseases.
To move forward, new studies with a larger number of participants, longer follow-up times, and in combination with biological markers (such as neuroimaging and inflammatory biomarkers) will be necessary. Only then will it be possible to answer the fundamental question: can cannabis slow down the progression of Alzheimer’s disease? We have taken an important step towards understanding this, but for now, the question remains unanswered.
Fabricio Pamplona não presta consultoria, trabalha, possui ações ou recebe financiamento de qualquer empresa ou organização que poderia se beneficiar com a publicação deste artigo e não revelou nenhum vínculo relevante além de seu cargo acadêmico.
Sapin de Noël, Piazza del Duomo, Milan (Italie).Thierry Gauquelin, CC BY
Souvent, le « sapin » de Noël n’est pas un sapin. Et il n’est pas lié historiquement à la naissance de Jésus de Nazareth. Deux botanistes se sont penchés sur ces paradoxes et nous aident à identifier les différents types d’arbres utilisés pour le 24 décembre.
Chaque année au mois de décembre, les « sapins » de Noël réapparaissent dans l’espace public, souvent richement ornementés et illuminés, mais également dans de nombreux foyers français où leurs branches les plus basses attendent d’abriter les cadeaux. Associé à la fête chrétienne de la nativité, cette tradition bien ancrée en Europe n’est pourtant pas d’origine religieuse, et le « sapin » de Noël est rarement un sapin ! Revenons donc en arrière pour tout comprendre à ces paradoxes.
Aux origines du sapin de Noël
Les origines du sapin de Noël restent incertaines et remontent probablement à la fin du Moyen Âge en Europe. Les premières mentions avérées apparaissent, indépendamment les unes des autres, au début du XVe siècle dans les régions germaniques de l’Ouest et du Nord, dans les pays baltes et, peu de temps après, en Alsace, où la première érection d’un sapin de Noël à Strasbourg date de 1492.Partout, en fin d’année, des conifères décorés de pommes, de pain d’épices et de guirlandes sont érigés sur la place publique.
Quelques années plus tard, des mâts ornés de lierre et de houx (des plantes à fleurs qui, comme la majorité des conifères, conservent leur feuillage en hiver) sont mentionnés en Angleterre.
Chaque fois, ce sont les corporations commerçantes qui sont à l’initiative de ce qui est baptisé « mai d’hiver » ou « mai de Noël ». En effet, cette pratique serait une transposition hivernale des « mais », ces arbres érigés au début du mois de mai pour célébrer la renaissance printanière de la végétation. Le terme « arbre de Noël » (Weihnachtsbaum) n’apparaît, lui, qu’en 1611, à Turckheim, en Alsace.
Il faut ensuite attendre le XVIe siècle pour que cette tradition, qui concernait uniquement la place publique, fasse son entrée dans la sphère privée. À Sélestat (Alsace), en 1521, un édit municipal autorise ainsi les habitants à couper de petits sapins pour Noël ; des conifères sont vendus sur les marchés à des particuliers pour qu’ils puissent les ramener chez eux et les décorer de pommes, de friandises et de gaufrettes.
La pratique doit connaître un succès rapide, puisque quelques décennies plus tard, les premières réglementations apparaissent pour limiter les abattages, comme à Fribourg (Suisse actuelle) en 1554, et les religieux dénoncent la généralisation d’un rite païen. Cela peut paraître paradoxal puisque le « sapin » de Noël est aujourd’hui souvent considéré comme un symbole religieux associé au christianisme.
La tradition du sapin de Noël sur la place Saint-Pierre, au Vatican (Rome), apparaît en 1982… Giuseppe Milo/Flick, CC BY
Mais cette christianisation d’un rite profane, qui ferait du sapin une évocation de l’Arbre de vie de la Bible, est très récente. Il a d’ailleurs fallu attendre 1982 pour que le premier sapin de Noël apparaisse place Saint-Pierre au Vatican.
Pour autant, l’arbre de Noël reste encore limité aux foyers aisés durant le XVIIIe siècle et ne devient une tradition populaire indissociable de la fête de Noël qu’à partir du XIXe siècle, aussi bien en Europe qu’aux États-Unis, où la tradition aurait été exportée en Pennsylvanie par des colons allemands à la fin du XVIIIe siècle.
À cette époque, l’arbre de Noël n’est d’ailleurs pas nécessairement un conifère, plusieurs feuillus sont utilisés, notamment des arbres fruitiers comme le pommier Christkindel, une variété de l’est de la France dont les petites pommes rouges écarlates auraient inspiré les boules de Noël une année où les pommes vinrent à manquer. Alors pourquoi le « sapin » de Noël ?
Sapin de Noël, à Dubaï (Émirats arabes unis), dans un centre commercial. CC BY
Un sapin de Noël qui en est rarement un
Aux origines, le « sapin » de Noël ne pouvait déjà pas être un sapin, puisqu’aucune espèce de sapin n’est autochtone dans les contrées qui ont vu naître cette tradition.
La seule espèce de sapin originaire d’Europe occidentale – hors région méditerranéenne – est le sapin blanc (Abies alba en latin), qui est naturellement absent de la moitié nord-ouest de l’Allemagne, des pays baltes et de toute l’Europe du Nord. Et à l’époque, l’être humain ne se livrait pas encore à des translocations d’espèces exotiques.
Forêt de sapin blanc dans les Vosges. Thierry Gauquelin, Fourni par l’auteur
Le « sapin » était donc surtout l’épicéa commun (Picea abies) et, plus occasionnellement, le pin sylvestre (Pinus sylvestris). Le véritable sapin blanc a cependant pu être utilisé de part et d’autre du Rhin, puisqu’il est indigène dans les massifs des Vosges (donc en Alsace), du Jura, des Alpes et des Pyrénées, mais probablement de manière assez marginale.
Aujourd’hui, en Europe, ce sont près de 50 millions d’arbres qui sont mis sur le marché pour les fêtes de fin d’année, dont 6 millions rien qu’en France. L’épicéa reste majoritaire, même si, en France, on lui préfère depuis quelques décennies le sapin de Nordmann (Abies nordmanniana), qui a l’avantage de ne pas perdre rapidement ses aiguilles, mais qui a l’inconvénient de ne pas dégager le même parfum de résine et d’être vendu plus cher.
Ainsi plus de 80 % des sapins vendus cette année en France sont du Nordmann, et l’épicea est, cette année, impossible à trouver dans la région de Marseille. Le sapin de Nordmann est une espèce exotique en France ; originaire d’une région qui s’étend de la Turquie aux montagnes du Caucase, il est largement planté désormais en France, notamment dans le Centre, pour être vendu à Noël, souvent un peu plus tôt que l’épicéa qui est indigène et également largement cultivé.
Ces dernières années on assiste aussi à une certaine diversification des conifères vendus comme arbres de Noël, puisque plusieurs espèces d’origine nord-américaine sont venues enrichir la palette :
de véritables sapins comme le sapin de Vancouver (Abies grandis) et le sapin noble (Abies procera), tous deux originaires de la côte ouest ;
des épicéas, en particulier le mal nommé « sapin » bleu du Colorado (Picea pungens), aux aiguilles bleu argenté et à l’odeur de pin ;
le « sapin » de Douglas (Pseudotsuga menziesii), dont le nom est trompeur, car il n’est ni un sapin ni un épicéa.
De manière amusante, l’Amérique du Nord, qui nous a fourni ces espèces de sapin à la mode, n’échappe pas à la tentation de l’exotisme ; ainsi, c’est le pin sylvestre européen qui a longtemps été l’espèce privilégiée outre-Altantique. Ce n’est que depuis les années 1980 que le Douglas et le sapin de Fraser (Abies fraseri) l’ont supplanté aux États-Unis, et le sapin baumier (Abies balsamea) au Canada.
Dans les régions tropicales et dans l’hémisphère Sud, cependant, d’autres arbres sont plébiscités. À La Réunion, par exemple, où Noël tombe pendant l’été austral, on utilise aussi bien des conifères (« pin » de Norfolk, Araucaria heterophylla ; « pin » colonnaire, Auraucaria columnaris ; « cèdre » du Japon, Cryptomeria japonica), que des feuillus tropicaux aux fleurs spectaculaires (flamboyant, Delonix regia) ou aux fruits comestibles (letchi, Litchi chinensis). Aux Antilles, on trouve également le filao (Casuarina equisitifolia) qui, malgré les apparences, n’est pas un conifère mais une plante à fleurs. Dans d’autres régions tropicales le pin de Monterey (Pinus radiata) et le cyprès de Lambert (Cupressus macrocarpa) sont également utilisés.
Un peu de botanique pour s’y retrouver
Parmi toutes ces espèces alors, comment s’y retrouver ? Comment savoir si ces « sapins » en sont véritablement ?
Commençons d’abord par rappeler que beaucoup des arbres que l’on voit à Noël appartiennent à la même grande famille des Pinacées qui comprend 11 genres et près de 250 espèces. On y trouve 50 espèces de sapins (Albies), 36 d’épicéas (Picea) et 130 de pins (Pinus). C’est la plus grande famille de conifères, dont les ancêtres sont apparus il y a près de 400 millions d’années, bien avant l’invention de la fleur dans l’histoire de l’évolution, plus de 200 millions d’années plus tard.
Les conifères font donc partie des Gymnospermes ou plantes « à ovule nu » qui, contrairement aux Angiospermes ne présentent ni fleur ni fruit. Parmi les Gymnospermes, une Pinacée est facilement reconnaissable à ses cônes femelles, plus connus sous le nom de « pommes de pin ». Ils sont constitués d’un axe central sur lequel des écailles ligneuses sont insérées de manière spiralée, portant sur leur face supérieure deux graines (les cônes mâles, plus discrets, sont en chatons).
Pour différencier les épicéas (genre Picea) des vrais sapins (genre Abies), quatre caractères peuvent être observés :
1 – les cônes femelles sont pendants chez les épicéas, mais dressés chez les sapins ;
À gauche, un sapin aux cônes dressés. À droite, un épicea aux cônes pendants. Forêt de Barèges, Pyrénées. Thierry Gauquelin, Fourni par l’auteur
2 – les cônes d’épicéas tombent entiers au sol, alors qu’ils se désintègrent sur l’arbre chez les sapins (donc jamais de cônes entiers au sol, juste des écailles) ;
3 – les rameaux des épicéas, une fois les aiguilles tombées, sont rugueux, car chacune des aiguilles est portée par une petite excroissance appelée pulvinus. Ils sont lisses chez les sapins, mais ornés de cicatrices rondes ;
4 – les aiguilles sont cylindriques plus ou moins anguleuses chez les épicéas, mais plates chez les vrais sapins.
Rameau de sapin de Nordmann à gauche (face supérieure et inférieure), et d’épicéa sur la photo de droite. Thierry Gauquelin/Guillaume Decocq, Fourni par l’auteur
Les vrais sapins peuvent être confondus avec les Douglas du genre Pseudotsuga. Ce genre comporte quatre espèces différentes, dont la plus connue et répandue est Pseudotsuga menziesii, d’origine nord-américaine). Toutes ont des aiguilles plates pourvues de deux bandes blanches à la face inférieure comme le sapin blanc. Mais chez les Douglas, les cônes sont pendants et tombent entiers, comme chez les épicéas, et les aiguilles ont toutes à peu près la même longueur, alors qu’elles sont de tailles très inégales chez les sapins.
Quant aux pins (Pinus), ils se différencient des genres précédents, qui ont tous des aiguilles solitaires, par leurs aiguilles normalement groupées par 2, 3 ou 5 au sein d’une gaine membraneuse basale caduque.
Rameaux de pin. Auguste Herbst, vers 1900. Musée de l’école de Nancy/Thierry Gauquelin, Fourni par l’auteur
Concernant les « sapins » de Noël ultramarins évoqués plus haut, il s’agit de conifères appartenant à d’autres familles botaniques, celle des Pinacées étant quasiment restreinte à l’hémisphère Nord.
Au sud de l’équateur, on trouve par exemple les espèces du genre Araucaria comme le « pin » de Norfolk et le « pin » colonnaire, qui ne sont donc pas des pins mais qui appartiennent à la famille des Araucariacées, exclusivement présente dans l’hémisphère Sud. Le « cèdre » du Japon, du genre Cryptomeria – qui n’est donc pas un cèdre, puisque non apparenté au genre Cedrus – et le cyprès de Lambert, du genre Cupressus qui, lui, est donc bien un cyprès, appartiennent à la famille des Cupressacées, au même titre que nos genévriers ou les séquoias et les thuyas.
On voit bien ici que les noms vernaculaires utilisés pour nommer les espèces végétales sont souvent une source de confusions, d’où l’importance du nom latin, qui en revanche est unique et attribué selon des règles très précises. C’est l’objectif de la science systématique, qui décrit, nomme (conformément au Code international de nomenclature biologique) et classe dans un système hiérarchisé les êtres vivants. Ce système prend en compte les liens de parenté entre les espèces, tels qu’ils sont reconstitués à partir des données génétiques, d’où son assimilation à un arbre généalogique du vivant.
Finalement, le seul « sapin » de Noël autochtone en France est donc l’épicea.
Dans tous les cas, les arbres commercialisés, que ce soient des Nordmann, des grandis, des pungens ou des épiceas sont issus de plantations. Et il faut être très exigeant sur leur mode de culture. Une filière bio est en train d’émerger garantissant qu’aucun traitement chimique n’est administré sur la plantation et qu’aucun désherbant ni aucun produit phytosanitaire n’est utilisé, pour le respect de la faune et de la flore locale.
Il ne faut pas oublier que les introductions d’essences exotiques ne sont pas dénuées de risques. Ainsi, même quand ils sont cultivés à proximité de la région où ils sont vendus, les « sapins » de Noël d’origine exotique peuvent servir de vecteurs pour des insectes ravageurs ou des agents pathogènes, susceptibles de s’attaquer aux conifères sauvages de nos forêts. Ainsi vaudrait-il mieux privilégier les essences autochtones.
La question est souvent posée aussi de savoir s’il faut préférer les arbres en pot ou les arbres coupés. Si les premiers sont réutilisables d’une année sur l’autre (tant qu’ils ne dépassent pas une certaine taille !) parce qu’ils peuvent être plantés ou mis en jauge dans un coin du jardin, des filières de recyclage ont aussi émergé pour les seconds, que ce soit pour le compostage ou pour lutter contre l’érosion ; par exemple la ville d’Anglet (Pyrénées-Atlantiques) installe des sapins de Noël récupérés sur le cordon dunaire de la plage pour ralentir l’érosion par la mer.
Sapins de Noël sur la plage d’Anglet (Pyrénées-Atlantiques). Thierry Gauquelin, Fourni par l’auteur
Et dans tous les cas, un « sapin » naturel, qu’il soit Abies ou Picea vaut toujours mieux qu’un sapin en plastique. Si ces derniers restent encore minoritaires en France, ils représentent plus de 80 % des arbres achetés aux États-Unis. Et ils sont aujourd’hui bien loin des tout premiers sapins artificiels initialement apparus en Allemagne au XIXe siècle, et alors confectionnés avec des plumes d’oie teintes en vert, rapidement remplacées par des poils d’animaux, puis par de l’aluminium.
Sinon, à défaut d’acheter aujourd’hui un sapin, pourquoi ne pas décorer des plantes d’intérieur tel qu’un ficus en pot. Certes, ce n’est pas un sapin ni même un conifère, mais l’arbre de Noël n’en a pas toujours été un au cours de l’histoire.
Les auteurs ne travaillent pas, ne conseillent pas, ne possèdent pas de parts, ne reçoivent pas de fonds d’une organisation qui pourrait tirer profit de cet article, et n’ont déclaré aucune autre affiliation que leur organisme de recherche.
Source: The Conversation – France (in French) – By Thierry Gauquelin, Professeur émérite, Institut méditerranéen de biodiversité et d’écologie marine et continentale (IMBE), Aix-Marseille Université (AMU)
Vieux chêne-liège, Andalousie (côte sud de l’Espagne).Thierry Gauquelin, CC BY
C’est un arbre pourvoyeur de multiples ressources depuis des millénaires et à la résilience remarquable lorsqu’il est confronté aux flammes. Le chêne-liège est cependant aujourd’hui menacé, d’un côté comme de l’autre de la Méditerranée, par le changement climatique ainsi que par sa surexploitation ou son abandon.
Alcornoque, surera, ballot, leuge, rusque, surier, suve, corcier… tous ces noms renvoient en fait à un seul et même arbre, le chêne-liège (Quercus suber) dont Pline l’Ancien (Ier siècle de notre ère) vantait déjà tous les mérites et utilisations.
Feuillage de chêne-liège, massif des Albères (Pyrénées). Thierry Gauquelin, Fourni par l’auteur
Ce chêne d’une hauteur moyenne de 10 mètres à 15 mètres, dont le feuillage persistant est assez semblable à celui du chêne vert (Quercus ilex), en diffère par son houppier étalé, ses grosses branches maîtresses – les charpentières – relativement horizontales et surtout par son écorce exubérante – le liège – un matériau exceptionnel à l’origine de l’intérêt que cet arbre a pu susciter et suscite encore.
C’est bien sûr l’utilisation du liège pour les bouchons, mais aussi dans le BTP en tant qu’isolant phonique et thermique avec aujourd’hui des avancées prometteuses dans le domaine de l’écoconstruction des bâtiments ou encore pour les fusées Ariane.
La fabrication de chaussures fait partie des nombreuses utilisations du liège, comme en témoigne cette gravure issue du livre le Liège et ses utilisations, de Henri de Graffigny (1863-1934). Gallica
Ainsi, les forêts de chêne-liège, qualifiées de systèmes socio-écologiques, ont été exploitées, soignées et modifiées depuis plus de trois mille ans, principalement pour ce liège, mais aussi pour leurs fruits, les glands, qui nourrissent ou ont nourri autant les humains que le bétail.
Dans sa région d’origine, la suberaie – c’est ainsi qu’on nomme une forêt de chêne-liège – a ainsi été largement favorisée par l’être humain. Observez nombre de suberaies des Albères, dans les Pyrénées ; vous verrez que les arbres sont peu ou prou alignés, c’est là le signe de la main humaine.
Malgré cette exploitation millénaire, ces suberaies peuvent héberger une biodiversité remarquable, notamment une faune spécifique et inféodée au bois mort et aux microhabitats que forment les vieux arbres souvent présents dans ces suberaies exploitées. La suberaie représente aussi l’habitat de prédilection de la tortue d’Hermann, unique espèce de tortue terrestre présente en France hexagonale et en Corse.
Au Maroc, ces écosystèmes abritent des petites mares temporaires, les dayas, à la biodiversité exceptionnelle, malheureusement menacées par le changement climatique et la surexploitation.
Daya dans la forêt de la Maamora (Maroc). Thierry Gauquelin, Fourni par l’auteur
Une répartition liée au climat et au sol
Le chêne-liège est endémique du bassin occidental de la Méditerranée, présent sur les deux rives sud et nord, du Maroc à l’Italie, mais il n’est pas limité au seul climat méditerranéen. On le trouve ainsi en grande quantité au Portugal, un des principaux producteurs de liège, mais aussi sur tout le littoral aquitain, comme dans la forêt des Landes. En France, ces suberaies recouvrent environ 70 000 hectares (ha) sur trois principaux secteurs : les massifs provençaux des Maures et de l’Esterel, le sud de la Corse et les Pyrénées-Orientales.
Autre caractéristique de ce chêne-liège, c’est une espèce exclusivement calcifuge, c’est-à-dire qu’elle fuit littéralement les terrains calcaires. C’est ce qui va régir sa répartition dans ce domaine méditerranéen. Ainsi, en Provence marseillaise calcaire, vous ne trouverez pas de chêne-liège. En revanche, passé Toulon, vers l’est, dans l’Esterel ou les Maures, le chêne-liège apparaît spontanément.
Extrait de la carte de la végétation de la France (feuille de Marseille), œuvre collective du CNRS. Le chêne-liège n’apparaît en orange que sur la partie est de la zone, sur les sols à roche-mère siliceuse. CNRS, Fourni par l’auteur
Les suberaies, derniers remparts contre l’incendie
Le chêne-liège est un arbre qui résiste fort bien à l’incendie du fait de cette couche épaisse d’écorce isolante, le liège, qui entoure le tronc. Si un incendie balaie une suberaie, le liège pourra être consumé sur plusieurs centimètres, mais rapidement des bourgeons dormants sous cette écorce se développeront et l’arbre repartira.
La périodicité de ces incendies doit évidemment rester raisonnable, sinon la biodiversité, notamment du sol, sera trop profondément affectée par ces perturbations récurrentes, compromettant ainsi le bon fonctionnement de ces forêts ; et la récolte de liège, qui ne peut se faire que tous les 8 ans à 15 ans, est dans tous les cas plus que compromise.
Dans le massif landais, où cette essence était autrefois bien représentée et exploitée, cette résilience à l’incendie et le rôle de pare-feu que peuvent jouer les suberaies doivent ainsi encourager des plantations massives de chêne-liège. Cela permet aussi de constituer des peuplements plus diversifiés donc plus résilients que les plantations monospécifiques de pin maritime.
La récolte du liège, essence même de la subériculture, est une affaire de spécialistes. Le chêne-liège est caractérisé par le développement exubérant de l’écorce, boursouflée et crevassée, ce fameux liège aux caractéristiques exceptionnelles. Mais cette écorce épaisse, observable sur les arbres qui n’ont pas été exploités, et qualifiée de « liège mâle », est inutilisable pour la fabrication de bouchons bien denses et réguliers. Elle sera par contre utilisée comme matériau isolant. Dans tous les cas, il faut donc enlever ce liège mâle ; cette opération s’appelle le « démasclage ».
Le rusquier (l’ouvrier qui lève l’écorce du chêne-liège) l’ôte à l’aide d’incisions verticales faites avec une hachette particulière, sur une hauteur d’environ deux mètres à partir du sol, séparant ainsi deux moitiés de l’écorce.
Démonstration de démasclage par Renaud Piazzetta, Institut méditerranéen du liège, massif des Albères (France). Thierry Gauquelin, Fourni par l’auteur Liège mâle et femelle du chêne-liège (Albères, France). Thierry Gauquelin, Fourni par l’auteur
Il faut procéder d’une manière très précautionneuse, de façon à ne pas abîmer l’assise qui donne naissance au liège. C’est un travail de spécialistes – lesquels se font de plus en plus rares et donc convoités. Le liège mâle enlevé, le tronc apparaît rouge vif.
Plaques de liège et bouchons à l’emporte-pièce. Thierry Gauquelin, Fourni par l’auteur
Un nouveau liège, bien dense, de très belle qualité, appelé le liège femelle, se forme alors. Au bout d’une période de huit à douze ans, on le récoltera quand son épaisseur permettra d’en extraire à l’emporte-pièce des bouchons de belle longueur.
À chaque démasclage, on montera un peu plus haut dans l’arbre. Quand des arbres présentent un démasclage très haut, jusqu’aux branches charpentières qui partent directement du tronc, on peut en déduire qu’ils sont très anciens, qu’ils ont 150 ans ou 200 ans, rarement plus d’ailleurs, car le chêne-liège n’est quand même pas une espèce très longévive.
C’est ensuite terminé sur le terrain. Les plaques de liège récoltées vont approvisionner les bouchonneries, comme les Bouchons Abel du Boulou (Pyrénées-Orientales), l’une des dernières en France à encore se fournir en liège local des Albères.
Récolte du liège, forêt de la Maamora (Maroc). Thierry Gauquelin, CC BY
Des suberaies aujourd’hui dépérissantes et menacées
Bien que particulièrement résilientes face aux incendies, les suberaies sont menacées dans toute leur aire de répartition du fait à la fois, selon les pays concernés, de leur surexploitation, de leur abandon ou encore du changement climatique.
Suberaie de la Maamora (Maroc). Thierry Gauquelin, Fourni par l’auteur
Ainsi au Maroc, la forêt de la Maamora, au nord-est de Rabat, considérée comme la plus grande suberaie d’un seul tenant au monde, est aujourd’hui réduite à 60 000 ha (sa surface était de plus de 100 000 ha dans les années 1950). Elle a subi de très fortes dégradations au cours de ces dernières décennies, notamment du fait de l’essor des plantations d’eucalyptus privilégié pour sa croissante rapide, sa résistance à la sécheresse et son utilisation pour la pâte à papier.
Suberaie dépérissante de Ben Slimane (Maroc). Thierry Gauquelin, Fourni par l’auteur
Cette suberaie reste néanmoins pourvoyeuse de nombreuses ressources pour les populations environnantes. Les dimanche de printemps dans la Maamora, près de Rabat, on verra comme cela tout à la fois le démasclage à la sauvette des arbres encore préservés, mais aussi le gaulage : les branches des chênes sont battues avec une longue perche pour faire tomber les fruits – des glands doux vendus ensuite bouillis à quelques dirhams le kilo pour le plus grand plaisir des enfants. On apercevera également le pâturage avec des bovins prélevant les feuilles encore tendres jusqu’à la hauteur que leur encolure tendue permet, la coupe par les bergers des branches afin de faciliter la tâche des animaux. Se joignent à ce tableaux quelques Rabatis pique-niquant sous les plus gros arbres à l’ombre cependant légère, après la récolte sauvage de bois mort pour cuire les brochettes.
Autant d’usages qui, au même titre que la biodiversité, sont menacés aujourd’hui par la sécheresse récurrente liée au changement climatique sur l’ensemble des suberaies allant de Rabat à Ben Slimane.
En France, c’est au contraire d’abord l’abandon progressif de l’exploitation des suberaies lié pour partie à la faible rentabilité de cette activité de subériculture qui menace ces écosystèmes. Cet abandon a rendu notamment les peuplements embroussaillés plus sensibles aux incendies.
D’autres facteurs aggravent ce déclin, comme une régénération naturelle très faible, des blessures dues à des démasclages mal réalisés ou l’installation d’insectes xylophages, tels que le coléoptère Platypus cylindrus qui peut localement pulluler et rapidement tuer des chênes-lièges. Et ce sont aussi aujourd’hui les canicules et sécheresses répétées liées au changement climatique qui aggravent ce dépérissement.
Tout ceci explique le classement comme vulnérables (VU) par l’UICN des suberaies méditerranéennes.
Relancer la subériculture en France en s’appuyant sur la science et sur la formation
Le maintien de ces systèmes socio-écologiques particuliers, à la biodiversité remarquable et jouant un rôle écologique majeur, notamment dans la lutte contre les incendies ou le maintien de sols fonctionnels, ne peut s’envisager qu’en intégrant une dimension socio-économique, tant ces deux composantes écologiques et économiques sont ici liées. Il s’agit alors de relancer économiquement la filière pour permettre notamment de préserver ces écosystèmes multifonctionnels. Différentes structures (Institut du liège, Subéraie varoise…) s’attachent aujourd’hui à cet objectif.
Ceci peut s’envisager notamment en privilégiant des circuits courts, économiquement rentables, en ciblant sans doute la production de bouchons haut de gamme, tout en explorant des nouvelles filières de valorisation du liège mâle.
Il s’agit aussi de favoriser la biodiversité, garante du bon fonctionnement de l’écosystème et de la qualité du liège récolté, et la résilience des peuplements aux aléas climatiques et notamment aux incendies.
Des travaux de recherche préliminaires menés par l’Institut méditerranéen de biodiversité et d’écologie marine et continentale (IMBE) dans le massif des Albères (Pyrénées) ont ainsi pu mettre en évidence qu’un débroussaillage et un pâturage des parcelles exploitées pour le liège favorisait une biodiversité floristique et faunistique caractéristique des milieux plus secs et plus lumineux et différente de celle que l’on retrouvait dans les parcelles laissées en libre évolution.
Cependant la pression exercée sur les suberaies doit rester raisonnée autant que possible. En effet, d’autres travaux menés par l’IMBE en collaboration avec l’Université Hassan-II de Casablanca ont montré quant à eux qu’une surexploitation de parcelles de chênes-lièges dans la région de Ben Slimane conduisait à une perte de biodiversité du sol et de sa capacité à séquestrer du carbone.
Mais la science seule ne suffit pas, et les suberaies nous montrent que nous avons de plus en plus besoin de professionnels et de chercheurs capables de travailler dans plusieurs disciplines et avec divers acteurs, en combinant les connaissances issues de différentes disciplines afin de contribuer à cet objectif commun de préservation et de valorisation.
Du point de vue académique, comprendre la suberaie comme système socio-écologique est un exercice complexe qui demande l’analyse des relations économiques, sociales et institutionnelles internationales, des savoir-faire traditionnels, sous des contraintes écologiques et climatiques profondément impactées par les particularités du XXIe siècle.
Ces écosystèmes constituent ainsi aujourd’hui « un terrain de jeu » idéal pour des formations universitaires académiques dispensées conjointement à Aix-Marseille Université et à l’Université Hassan-II de Casablanca où l’enseignement de la transdisciplinarité est réalisé en ancrant les apprentissages dans un problème concret.
Étude de la faune du sol par les étudiants de l’Université de Marseille et de Casablanca ; suberaie des Pyrénées-Orientales. Thierry Gauquelin, Fourni par l’auteur
Cependant, dans l’Hexagone, malgré la banalité des bouchons de liège, les relations étroites que les habitants des Albères, des massifs des Maures et des Landes entretiennent avec ces suberaies sont aujourd’hui anecdotiques, alors qu’une meilleure connaissance de ce patrimoine, à la fois biologique et culturel, est un préalable à ce nouvel essor.
Anne Bousquet-Mélou a reçu des financements de la fondation amidex et de l’institut méditerranéen pour la transition environnementale de l’université d’Aix-Marseille
Irene Teixidor-Toneu a reçu des financements de l’agence nationale de la recherche (ANR).
Mathieu Santonja a reçu des financements de l’Agence nationale de la recherche (ANR), France 2030 et l’Union Européenne.
Thierry Gauquelin ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d’une organisation qui pourrait tirer profit de cet article, et n’a déclaré aucune autre affiliation que son organisme de recherche.
A reproduction of a postcard marking empire day celebrations in Bristol in 1912. Shutterstock/Igor Golovniov
If you wander through Glasgow Green, you’ll encounter the Doulton fountain, a gaudy terracotta tribute to empire that features “native” and colonial figures in national dress holding out the produce of their lands to the imperial centre. Like thousands of imperial monuments across Britain, the Doulton Fountain is neither widely celebrated nor widely denounced. It is part of the everyday backdrop.
That quiet coexistence says a lot about Britain’s relationship with its imperial past. Empire is everywhere – cast in stone, threaded through schoolbook stories and family lore – but rarely front-and-centre in political debate. In a new article in the British Journal of Political Science, Daniel Devine and I set out to answer two questions: what do Britons actually think about the empire, and do those views matter politically?
To answer these questions, we built a measure of imperial nostalgia using survey questions on attitudes to empire. We asked people how much they agreed with statements like “the British Empire had a great civilising effect” and “the British Empire was responsible for many atrocities”.
Across two polls in late 2023 and mid-2024, we found Britain both divided and unsure about its imperial past. Net support swings from −50 points when asked whether the empire was “responsible for many atrocities” (62% agree, 12% disagree) to +21 points on whether it had a “civilising effect” (44% agree, 23% disagree).
Between a quarter and 40% of respondents chose the “neither” or “don’t know” options, showing that there is substantial ambivalence in attitudes. Taken together, opinion about empire tilts slightly negative: more critical than celebratory, but far from a blanket rejection.
Demographically, imperial nostalgia rises with age and falls with education. It is higher among men and white British respondents, and notably lower in London and Scotland. In short, it behaves like a form of cultural conservatism. However, we find that it forms its own dimension of opinion, distinct from authoritarianism and nationalism. That distinctiveness matters, because it implies politicians may be tapping something different when they invoke empire, as when Boris Johnson recited The Road to Mandalay on a visit to Myanmar.
How imperial views relate to voting
We found that imperial nostalgia connects quite significantly with partisan politics. Supporters of Labour, the Liberal Democrats and the Greens are, on average, more critical of empire. Conservative and Reform supporters are more nostalgic about it. This is perhaps predictable but the strength of the relationship between views on empire and party preference was a surprise – it was stronger than left–right economic values, for example.
The result survives more demanding tests. Imperial nostalgia remains an important positive predictor for Conservative and Reform support, and a negative predictor of Green support, when we control for respondents’ other political attitudes and identities.
The link remains when we add a separate measure of general nostalgia (“life was better 50 years ago”), demonstrating that imperial nostalgia isn’t just another name for backward-looking mood. In fact, the two nostalgias diverge in their effects. General nostalgia negatively predicts Conservative support but positively predicts Reform support. Imperial nostalgia boosts both the Conservatives and Reform.
However, this is not to say that voters want their politicians to go on about empire. In fact, when we asked respondents to choose between hypothetical parliamentary candidates, they opted for ambivalence in their representatives. When presented with a conservative who thought empire had a “civilising effect”, a progressive who said empire was “responsible for many atrocities” and a third candidate with mixed views incorporating both, the latter was the most popular.
While a conservative position on empire neither helps nor hurts a candidate overall, a progressive stance actually reduces support by about five percentage points. In other words, criticism is the least popular position when it comes to politicians, even though most respondents adopted such a critical view when asked about their own opinions of empire.
The picture sharpens when we examine the results separately by respondents’ ideology and party. Conservative and culturally conservative voters punish the critical “atrocities” stance strongly, while cultural liberals offer little offsetting reward for it.
Studied silence on empire
So for political parties, openly criticising empire is not a winning strategy. It yields only minimal gains on the left while antagonising and mobilising voters on the right.
That asymmetry helps explain the studied quiet we’re currently experiencing. Steering around an issue is considered the best course of action if it divides the public and risks energising opponents more than supporters.
Our study suggests that imperial nostalgia is like a submerged current in British politics. It shapes where parties can safely sail even if they rarely talk about the tide. But we think it’s possible that the current could resurface.
Imperial nostalgia correlates strongly with support beyond the main parties: positively with Reform and negatively with the Greens. With Britain’s party system in unprecedented flux, a challenger could weaponise the issue to split opponents and mobilise a base.
And since younger Britons hold more notably critical views of empire, their entry into the electorate could make debates about the past more electorally decisive and therefore worth campaigning on. Our experiment suggests a sharp backlash from conservatives will ensue, setting the stage for a fresh culture-war divide.
Even without these two factors, it remains the case that backward-looking narratives resonate more strongly in periods of perceived national decline. So if the current stagnation persists, imperial nostalgia could surface from background mood to foreground politics.
Want more politics coverage from academic experts? Every week, we bring you informed analysis of developments in government and fact check the claims being made.
Christmas is often considered a time of connection, warmth and belonging. That’s the script, anyway. But for many people, the reality feels different; isolating, emotionally weighted and filled with comparisons that sting.
Whether you’re spending Christmas alone, navigating grief, or simply don’t feel “festive,” it can feel like you’ve slipped out of sync with the rest of the world. However, that feeling isn’t the same as being alone. Loneliness, isn’t about the number of people around you. It’s about connection, and the absence of it.
This time of year intensifies emotional experience. Rituals such as decorating a tree or watching a favourite film may bring up memories. These could be of people, or they could be of former versions of ourselves.
We measure time differently in December, a phenomenon psychologists refer to as “temporal anchoring”. The season acts as a golden thread spanning our lives, pulling us back to the past. We often use it to reflect on what we’ve lost, who we’ve become, and what didn’t happen. It can cut deeply.
It is a sharp counterpoint to the cultural messaging: people coming together, the push to be joyful and the idea that gratitude must prevail. It’s not just tinsel that is expected to sparkle. We are, too.
Some people are more vulnerable at this time of year, particularly those in flux or transitioning. A recent breakup, moving house, a medical diagnosis or redundancy can often lead to feeling emotionally unanchored. Others carry complex feelings about family, grief or past trauma, which make forced joy or cheerfulness jarring.
Personality plays a role too. People high in traits such as neuroticism or socially prescribed perfectionism can be more vulnerable to distress and loneliness when life does not live up to their expectations.
Your brain on loneliness
Studies have shown that chronic loneliness can increase stress hormones such as cortisol, impair immune function and even affect cardiovascular health. Social neuroscientist John Cacioppo described loneliness as “a biological warning system” that our need for connection isn’t being met.
Loneliness, though, is a normal human response. It is a reaction to a mismatch between our desired social experience and our reality. Self-discrepancy theory helps explain why this mismatch causes emotional pain. When there’s a gap between who we are and who we feel we should be, whether it is socially, emotionally or even seasonally, discomfort follows. Christmas, with all its trimmings, amplifies that gap.
That said, being alone at Christmas doesn’t automatically mean something’s wrong.
In fact, it might be exactly what you need.
For many, this time can be a rare opportunity for space, stillness and healing. It
might be the only time of year when you get the space to hear your own thoughts, reflect or reset. Choosing solitude purposefully can be deeply restorative.
Connecting with yourself can be just as important as connecting with others.
Research into self-determination theory also highlights autonomy, competence and relatedness as core psychological needs.
Autonomy, in particular, means honouring your own choices, not other people’s expectations. For example, choosing to spend the day quietly reading, cooking for yourself, or creating a personal ritual supports both autonomy and competence. These acts reinforce your ability to care for yourself and reduce the pressure to seek validation from others.
Philosophers such as 19th-century Danish thinker Søren Kierkegaard and ancient stoic Epictetus emphasised the importance of tuning into your own inner life rather than being governed by external forces. They remind us that authenticity doesn’t come from performing joy for others, but from noticing what we need and choosing to honour it.
The key is alignment. Do what nourishes you, not what performs well on
Instagram, and let the societal pressures wash over you rather than be driven by
them.
So what can help?
Trying to “fix” loneliness with a to-do list isn’t the answer. It’s about tuning into what you need. These approaches are rooted in psychological and philosophical insight. They are not quick fixes.
1. Let yourself feel it
Loneliness hurts. It’s okay to name it. Pushing it away rarely works. Accepting and sitting with it can be the first step toward softening its grip.
2. Create micro-rituals
Small routines bring meaning and structure. Brew a
particular tea. Rewatch a film that resonates. Light a candle for someone you miss. Rituals connect you to something larger but also connect you to yourself.
3. Reframe connection
Closeness doesn’t have to mean crowds. It might mean sending a message, joining a quiet online space or simply being present with yourself. Journaling, voice notes or reflective walks can all be forms of inward connection.
4. Celebrate your uniqueness
You are not a statistic. You don’t need to aim for the “average” mental health baseline. Your emotional life is yours alone. A little variation, a little eccentricity, these are signs of being alive.
5. Find what works for you
There’s no one right way to do Christmas. Whether it’s a solo walk, a day in pyjamas, or calling one person you trust, the point is to honour your individuality.
If you’re feeling out of step this Christmas, that doesn’t make you broken. It makes you aware. You’re noticing what’s missing; you are listening. That’s not weakness, it’s one of the greatest sources of wisdom.
In The Book of Disquiet, Portuguese poet and philosopher Fernando Pessoa wrote: “To feel today what one felt yesterday isn’t to feel – it’s to remember today what was felt yesterday, to be today’s living corpse of what yesterday was lived and lost.”
It’s a stark image, but a truthful one. At Christmas, we often try to summon old
feelings, those of joy, warmth, and belonging, as if they can be reactivated on
command. But what if we didn’t force it? Christmas doesn’t have to be remembered joy. It can be present truth.
Loneliness isn’t something to be solved or suppressed. It’s a companion on the
journey inward.
And sometimes, the most meaningful connection we can make is with ourselves.
This article features references to books that have been included for editorial reasons, and may contain links to bookshop.org. If you click on one of the links and go on to buy something from bookshop.org The Conversation UK may earn a commission.
Paul Jones does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
“We cannot negotiate with the melting point of ice.” That’s the message from more than 50 leading scientists who study the Earth’s frozen regions, published in the latest annual State of the Cryosphere report.
In the past year alone, the vast polar ice sheets in Greenland and Antarctica are likely to have shed around 370 billion tonnes of ice, with a further 270 billion tonnes from the 270,000 mountain glaciers around the world, some of which are disappearing altogether.
In February 2025, global sea ice extent reached a new all-time minimum in the 47-year satellite record. Elsewhere, perennially frozen ground (called permafrost) continues to thaw, releasing additional greenhouse gas emissions each year that are roughly equivalent to the world’s eighth-highest-emitting country.
The warning lights from the cryosphere have been flashing red for several years, and governments ignore this at their peril.
Melting ice is driving an acceleration in the rate of sea-level rise, which has doubled to 4.5mm per year over the last three decades. If this acceleration continues, sea-level rise will reach around 1cm per year by the end of this century – a rate so high that many island and coastal communities will be forced to move.
The loss of mountain glaciers will affect billions of people who rely on their meltwater for agriculture, hydropower and other human activities; and the damage caused to infrastructure by Arctic permafrost thaw has been estimated to cost US$182 billion (£137 billion) by 2050 under our current emissions trajectory.
Negotiations based on ‘best available’ science
In an effort to reduce the risks and effects of climate change, including those from the cryosphere described above, the Paris climate agreement was adopted by 195 countries at the annual UN climate summit in 2015, with the aim of limiting “the increase in global average temperature to well below 2°C above pre-industrial levels” and pursue efforts “to limit the temperature increase to 1.5°C”.
Its implementation should be based on and guided by the “best available science”. That includes evidence provided by the Intergovernmental Panel on Climate Change (IPCC), a group created by the UN to provide governments with regular assessments of the scientific basis of climate change, its impacts and options for adaptation and mitigation.
Yet recent climate negotiations, including at the UN climate summit in Brazil in November 2025 (Cop30), have seen some countries – largely fossil fuel producers – push back on previously standard language endorsing the IPCC as a source of the “best available science”.
As cryosphere scientists who regularly attend the UN’s climate summits, we have noticed recent efforts to downplay, confuse and dilute some of the latest scientific findings, especially from the cryosphere. We find this alarming.
At Cop30, observations about the complete loss of glaciers in two countries (Slovenia and Venezuela) were removed from the final draft text. Other shocking scientific findings about “irreversible changes to the cryosphere” were diluted to a rather vague “need to enhance observations and address gaps in the monitoring of the hydrosphere and the cryosphere”.
This tactic to obfuscate the science is not new, but has been increasingly used over recent years, during which the indicators of climate change and its consequences on the cryosphere have become increasingly obvious to scientists.
At Cop30, climate negotiators from several countries expressed disappointment and concern that the role of the IPCC as the best available science was not highlighted alongside some of the more alarming scientific findings, with an intervention from the UK capturing this frustration.
While the final overarching summary text from Cop30 – the Mutirão decision – references the IPCC as the source of the best available science, and contains some strong language around the need to limit warming to 1.5°C, rather than 2°C, these look like empty words when the same document fails to even mention “fossil fuels”. Emissions from fossil fuels will result in 2.6°C of warming by 2100, without urgent action.
Indeed, the final text from Cop30 is the first to explicitly reference a temperature “overshoot”, reiterating the need “to limit both the magnitude and the duration of any temperature overshoot”. Most scientists agree that overshoot is now inevitable, but that 1.5°C increase remains the legal and ethical imperative for a long-term global temperature target.
However, some scientists – including ourselves – would argue that even this is too high, committing us to losing around half of the world’s mountain glaciers and several metres of sea-level rise from the polar ice sheets.
Among the dire warnings, a recent study offers hope that it is still possible to curtail warming in the next 15 to 20 years, peaking at an increase of around 1.7°C in the 2040s before declining to an increase of 1.5°C and then 1.2°C by the end of the century. But that requires rapid and deep cuts in emissions from now on.
Climate negotiations may move at a glacial pace, but the irony is that the pace of glacier change is rapidly overtaking our ability to adapt to it and protect the most vulnerable people. The science is clear. But the perils of ignoring it are even clearer.
Don’t have time to read about climate change as much as you’d like?
Chris Stokes receives funding from the the Natural Environment Research
Council (NE/R000824/1).
Florence Colleoni has previously received some funding from national Italian Programma Nazionale sulle Ricerche in Antartide (PNRA) and currently receives funding from the High-Computing Performance-TRES programme from the Italian Ministry of Research. She is affiliated with the Scientific Committee on Antarctic Research for which she serves as co-chief officer of the science research programme INSTANT.
James Kirkham has previously received funding from the Natural Environment Research Council. He is currently affiliated with the International Cryosphere Climate Initiative (ICCI) and regularly works with countries in the context of the UNFCCC.
A reproduction of a postcard marking empire day celebrations in Bristol in 1912. Shutterstock/Igor Golovniov
If you wander through Glasgow Green, you’ll encounter the Doulton fountain, a gaudy terracotta tribute to empire that features “native” and colonial figures in national dress holding out the produce of their lands to the imperial centre. Like thousands of imperial monuments across Britain, the Doulton Fountain is neither widely celebrated nor widely denounced. It is part of the everyday backdrop.
That quiet coexistence says a lot about Britain’s relationship with its imperial past. Empire is everywhere – cast in stone, threaded through schoolbook stories and family lore – but rarely front-and-centre in political debate. In a new article in the British Journal of Political Science, Daniel Devine and I set out to answer two questions: what do Britons actually think about the empire, and do those views matter politically?
To answer these questions, we built a measure of imperial nostalgia using survey questions on attitudes to empire. We asked people how much they agreed with statements like “the British Empire had a great civilising effect” and “the British Empire was responsible for many atrocities”.
Across two polls in late 2023 and mid-2024, we found Britain both divided and unsure about its imperial past. Net support swings from −50 points when asked whether the empire was “responsible for many atrocities” (62% agree, 12% disagree) to +21 points on whether it had a “civilising effect” (44% agree, 23% disagree). Between a quarter and 40% of respondents chose the “neither” or “don’t know” options, showing that there is substantial ambivalence in attitudes. Taken together, opinion about empire tilts slightly negative: more critical than celebratory, but far from a blanket rejection.
Demographically, imperial nostalgia rises with age and falls with education. It is higher among men and white British respondents, and notably lower in London and Scotland. In short, it behaves like a form of cultural conservatism. However, we find that it forms its own dimension of opinion, distinct from authoritarianism and nationalism. That distinctiveness matters, because it implies politicians may be tapping something different when they invoke empire, as when Boris Johnson recited The Road to Mandalay on a visit to Myanmar.
How imperial views relate to voting
We found that imperial nostalgia connects quite significantly with partisan politics. Supporters of Labour, the Liberal Democrats and the Greens are, on average, more critical of empire. Conservative and Reform supporters are more nostalgic about it. This is perhaps predictable but the strength of the relationship between views on empire and party preference was a surprise – it was stronger than left–right economic values, for example.
The result survives more demanding tests. Imperial nostalgia remains an important positive predictor for Conservative and Reform support, and a negative predictor of Green support, when we control for respondents’ other political attitudes and identities.
The link remains when we add a separate measure of general nostalgia (“life was better 50 years ago”), demonstrating that imperial nostalgia isn’t just another name for backward-looking mood. In fact, the two nostalgias diverge in their effects. General nostalgia negatively predicts Conservative support but positively predicts Reform support. Imperial nostalgia boosts both the Conservatives and Reform.
However, this is not to say that voters want their politicians to go on about empire. In fact, when we asked respondents to choose between hypothetical parliamentary candidates, they opted for ambivalence in their representatives. When presented with a conservative who thought empire had a “civilising effect”, a progressive who said empire was “responsible for many atrocities” and a third candidate with mixed views incorporating both, the latter was the most popular.
While a conservative position on empire neither helps nor hurts a candidate overall, a progressive stance actually reduces support by about five percentage points. In other words, criticism is the least popular position when it comes to politicians, even though most respondents adopted such a critical view when asked about their own opinions of empire.
The picture sharpens when we examine the results separately by respondents’ ideology and party. Conservative and culturally conservative voters punish the critical “atrocities” stance strongly, while cultural liberals offer little offsetting reward for it.
Studied silence on empire
So for political parties, openly criticising empire is not a winning strategy. It yields only minimal gains on the left while antagonising and mobilising voters on the right.
That asymmetry helps explain the studied quiet we’re currently experiencing. Steering around an issue is considered the best course of action if it divides the public and risks energising opponents more than supporters.
Our study suggests that imperial nostalgia is like a submerged current in British politics. It shapes where parties can safely sail even if they rarely talk about the tide. But we think it’s possible that the current could resurface.
Imperial nostalgia correlates strongly with support beyond the main parties: positively with Reform and negatively with the Greens. With Britain’s party system in unprecedented flux, a challenger could weaponise the issue to split opponents and mobilise a base.
And since younger Britons hold more notably critical views of empire, their entry into the electorate could make debates about the past more electorally decisive and therefore worth campaigning on. Our experiment suggests a sharp backlash from conservatives will ensue, setting the stage for a fresh culture-war divide.
Even without these two factors, it remains the case that backward-looking narratives resonate more strongly in periods of perceived national decline. So if the current stagnation persists, imperial nostalgia could surface from background mood to foreground politics.
Want more politics coverage from academic experts? Every week, we bring you informed analysis of developments in government and fact check the claims being made.
It’s that time of year again, and retailers are pulling out all the stops to get us spending – from Black Friday to new year’s sales.
The average Briton expects to shell out around £300 on Christmas gifts. But as budgets tighten, more people are turning to buy-now-pay-later schemes to spread the cost over time. Our research has uncovered how these services have become woven into many people’s festive spending.
One shopper told us how a brand’s email about an early Black Friday discount led her to buy items she had been considering for a while, as the reduced prices made the decision feel too good to pass up.
But not everyone can afford this seasonal spending spree. About a third of Britons worry about the financial hit of Christmas. Many turn to credit cards or overdrafts. And that’s now being joined by the fast-growing buy-now-pay-later options to make ends meet.
One man said he had built up about £120 in buy-now-pay-later debt after picking up “bits and bobs” for Christmas, and hoped his total spending wouldn’t climb beyond £500 this year.
By the end of 2025, more than half the UK population will have tried buy-now-pay-later. It has become mainstream across all ages and incomes, reaching this status in just over a decade. This is much faster than credit cards, which took decades to catch on. This Christmas, buy-now-pay-later’s influence is impossible to miss.
Frictionless credit at the click of a button
But why has its use spread so quickly? One reason we discovered from our interviews with shoppers is because it’s incredibly easy to access. Minimal checks and balances mean almost anyone can sign up, though regulation is on the way.
One woman said what drew her to buy-now-pay-later was how effortless it felt. The service was readily available, convenient and allowed her to manage costs she otherwise might not cover upfront.
Buy-now-pay-later isn’t just easy, though – it’s everywhere. Whether you’re shopping online, in-store, at global brands, or with local sellers, buy-now-pay-later is available at the checkout. Some even feel it’s safer than entering card details online: “I believe, or I see it as a safer way to pay in the sense … prevents me from entering in my card details … on the website.”
Buy-now-pay-later providers also sweeten the deal with special promotions, and their apps let you use the service even when stores don’t officially offer it. For many, it’s become an essential part of holiday shopping. As one participant told us: “Now the festive season approaches, the utility of buy-now-pay-later schemes becomes especially evident in my Christmas budgeting.”
For some people, buy-now-pay-later is a lifeline for impulse buys and last-minute must-haves. One respondent explained that it had made her recent clothes shopping easier. She had ordered multiple outfits for a Christmas event, kept just one and returned the rest. She said it was reassuring that no payment had been taken while she waited to make her final choice.
Buy-now-pay-later also helps people stretch their budgets, especially when giving gifts is tied to family expectations or self-indulgence. An interviewee told us that she often uses it in the run up to Christmas, when she needs to buy several gifts but doesn’t have the funds available all at once. To her, it made the service particularly useful during the festive period.
Still, not everyone is comfortable borrowing to buy gifts, as one person told us: “When I buy gifts, I prefer to have them paid instantly as one-off payments as opposed to over time because I think in my head when I’m giving the gift, I don’t want to think about, you know, two months later I’m still paying for that gift.”
Others see a downside to the buy-now-pay-later habit: “What I don’t really like about Klarna at times is the fact that it’s kind of addictive … I can feel myself getting attached [to] the idea of paying later rather than straight away, because I feel like I’m technically not spending.”
The lure of ‘future money’
Buy-now-pay-later can also appear to soothe the sting of spending. Instead of feeling the pain at checkout, you get to delay it, and sometimes until well after the festive glow has faded.
Young people, especially generation Z (born between 1995 and 2009) and millennials (born between 1980 and 1994), often see buy-now-pay-later as a modern way to access their “future money”, quite unlike the old-school credit card.
But the bill always comes eventually. Overdoing it with buy-now-pay-later can leave you struggling to keep up with repayments, especially if you’ve bought more than you can afford.
Our research found that frequent users are more likely to incur late fees, interest charges and have current money worries. Young users may lack financial skills, but they’re optimistic about bouncing back. Sometimes too optimistic.
We all want a joyful Christmas. Buy-now-pay-later can help, but it’s no magic wand. Rely on it too much, and you may start the new year with more debt than you bargained for.
Anita Lifen Zhao has received funding from the British Academy. She is an Associate Professor in Marketing at the School of Management, Swansea University. The University is an affiliate member of the Money Advice Liaison Group.
Philippa Ward has received funding from the British Academy. She is a Professor of Marketing at the School of Business, Computing and Social Sciences, University of Gloucestershire. The University is an affiliate member of the Money Advice Liaison Group.
Ruffin Relja is a Senior Lecturer in Marketing at the School of Business, Computing and Social Sciences, University of Gloucestershire. The University is an affiliate member of the Money Advice Liaison Group.
For people living in the EU, the price of their next car, home renovation and even local produce may soon reflect a climate policy that many have never even heard of. This new regulation, which comes fully into force on New Year’s Day, does not just target heavy industry – it affects everyday goods which now face an added carbon cost when they enter Europe.
The carbon border adjustment mechanism (CBAM) puts a carbon price on many imported goods – meaning that EU-based importers will pay for the greenhouse gases emitted during the production of certain carbon-intensive materials.
If goods come from countries with weaker climate rules, then the charge will be higher. To sell to the EU, producers will effectively need to show their goods aren’t too carbon intensive.
The goal is to prevent companies from relocating their production to places with looser regulations, ensuring fair competition between EU and non-EU companies, while incentivising global decarbonisation.
After a trial phase, full payment obligations begin on January 1 2026, when importers will need to buy CBAM certificates to cover the embedded emissions in goods such as iron and steel, aluminium, cement, fertilisers, hydrogen and (eventually) electricity.
Although it is an EU climate policy, CBAM looks set to be a gamechanger for global trade. Countries that rely on EU exports may need to make costly investments in cleaner technologies and better emissions tracking, or risk losing market share. The UK government plans to introduce its own version of CBAM in 2027 – although how this links to the EU’s is yet to be decided.
A positive shift is already underway: more and more companies are now measuring and reporting their emissions accurately, responding to the growing demand for reliable carbon data. At the same time, an increasing number of countries are introducing their own carbon pricing systems to stay aligned with the EU and protect the competitiveness of their exports.
Morocco is a prominent example: its 2025 finance law gradually introduces a carbon tax from January 2026. As Moroccan firms will already pay a carbon price domestically, their exports are likely to avoid additional CBAM charges at the EU border, helping them remain competitive.
In many countries, CBAM is also accelerating interest in renewable energy and greener industrial processes. Some see it not as a threat, but an opportunity to attract investment and position themselves as low-carbon manufacturing hubs.
However, this mechanism is still controversial. For businesses, CBAM is complex and administratively heavy. Firms need robust systems to measure embedded emissions, collect data from suppliers and produce environmental product declarations. Many will also need new renewable energy contracts to cut their carbon footprint.
Around the world, CBAM has faced strong criticism. India and China describe it as “green protectionism”, arguing that it puts unfair pressure on developing economies. At the same time, the EU has not yet created dedicated funding to help exporters in lower-income countries adapt. Without this support, the mechanism may not achieve the desired results.
What about consumers?
Although CBAM is mainly aimed at industry, its ripple effects will reach consumers in the EU. Importers are unlikely to absorb the full additional cost, meaning prices are likely to rise – particularly for goods that rely heavily on steel, aluminium or cement. This could mean Europe sees higher costs for cars, home appliances, electronics, building materials and, indirectly, food production (through fertilisers).
At the same time, CBAM may bring more transparency. Because importers must report the emissions embedded in their goods, consumers may eventually have clearer information about the climate impact of what they buy.
The mechanism will also generate EU revenues from certificate sales. These are expected to support vulnerable households in many European countries, as well as funding clean technologies and improving energy efficiency. How the funds are used will be crucial to public acceptance of Europe’s new carbon tax.
Even before full implementation, CBAM is already reshaping supply chains and influencing government policies far beyond Europe’s borders. It may trigger trade disputes, push exporters to adopt carbon pricing, and highlight the need for more climate finance to support developing countries undergoing green industrial transitions.
For many European consumers, it’s likely to mean gradual price increases – and potentially, more climate-conscious purchasing decisions. Behind the scenes, it marks a significant shift in how global trade accounts for carbon – and how climate policy reaches into people’s everyday lives.
Don’t have time to read about climate change as much as you’d like?
Simona Sagone does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
Source: The Conversation – UK – By Clare Anderson, Professor of Sleep and Circadian Science, University of Birmingham
Christmas is supposed to be restful, yet somehow it ends up being one of the worst times of year for sleep. Between late nights, travel, one too many eggnogs and all that excitement, your sleep schedule doesn’t stand a chance – and neither does your mood, safety or health. Here are a dozen sneaky ways Christmas sabotages your sleep and what you can do about it.
Many adults routinely sleep less than the recommended seven hours. Nightly sleep loss of even one hour quickly takes a major toll. Sleeping less than six hours a night can cause dangerous levels of sleepiness after just two weeks, making end of year exhaustion real, and the Christmas break an ideal time to catch up on lost sleep.
Christmas Eve excitement sends stress hormones soaring in kids (and let’s be honest, adults too), making it nearly impossible to drift off. Paradoxically, sleepy children often become hyper rather than drowsy – turning bedtime into a battle. When children stay up later, this results in parents staying up later. This doesn’t simply delay sleep, it also shortens it, reducing total sleep time by an average of 33 minutes for each hour that bedtime is delayed.
While others are celebrating, retail, healthcare and other essential workers are grinding through marathon shifts that wreak havoc on sleep. Shifts lasting longer than ten hours increase the risk of accident and injury by 13%, while those involving night work increase it by 28%. Put those together (long shifts overnight) and it’s a recipe for disaster. Sleeping during the day and being awake at night is already a challenge for many shift workers, but even more so at Christmas.
6. The hidden burden of Christmas travel
In all the Christmas excitement, it’s easy to forget how risky travel can be when you’re tired. Sleepiness contributes to around 17% of fatal vehicle accidents – and long journeys, international travel, reduced sleep and sleeping in unfamiliar environments all make things worse.
7. Christmas lights paradox
For those in the northern hemisphere, winter brings lower light levels during the day, yet bright Christmas displays light up the night sky – and our brain. Indoor lighting that is too dim during the day and too bright at night can disrupt circadian rhythms and sleep, making us feel more tired and less happy. While sleeping under Christmas lights may put you in the festive mood, it can disrupt your heart rate during sleep and affect your blood sugar in the morning.
8. Alcohol and the myth of the silent night
Yes, alcohol helps you nod off faster, but then it sabotages your sleep by messing with your brain chemistry and making breathing problems worse. You won’t even remember these disruptions (you need to be awake for several minutes to form a memory), but you’ll definitely remember the hangover.
9. Christmas napping
A Christmas Day nap can be a tradition for many families – especially grandpa. On average, people sleep about 5% more on Christmas Day. That extra 24 minutes of sleep over the holidays can help fight off common colds and other bugs. Christmas really is the time to indulge … in sleep.
10. More than an empty stocking
Money worries, heightened expectations and increased loneliness can all trigger Christmas anxiety. When you’re anxious, there’s a 90% increased risk that you’ll struggle to fall or stay asleep – and poor sleep makes anxiety worse. Protecting your sleep and helping others protect theirs can help prevent this vicious circle.
11. The pleasure and pain of New Year’s Eve
New Year’s Eve is the worst night of the year for sleep – most people go to bed 90 minutes later than usual, and it shows. More traffic accidents than usual happen on New Year’s Day, so if you’re exhausted, skip anything that requires alertness.
12. A gift to yourself
If on the twelfth day of Christmas your wish is for a good night’s sleep and staying safe and well, here are some top tips:
Keep sleep and wake timing consistent where possible, and aim for at least seven hours of sleep.
Naps are a perfect way to refresh and restore, but keep them short (20-30 minutes) and early (before 3pm).
Moderate your alcohol and heavy food intake.
Manage light exposure. Maximise natural daylight and avoid artifical light, including bright screens (phones, tablet computers, laptops) at night. Cosy, warm, dim Christmas lights are fine, but turn them off before bed.
Support children’s sleep. Keep the bedtime routine consistent and manage excitement.
Take special care when travelling. Think three S’s: Seven hours of sleep. Switch drivers or rest every two hours. Stop if you feel sleepy.
Clare Anderson currently receives funding from UK (ESRC, EPSRC) and Australian (ARC, NHMRC) Research Councils, Transport Accident Commission and Takeda Pharmaceutical.
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