CaixaForum Madrid delves into the life of mammoths

The corporate director of the Culture and Science Area of the "la Caixa" Foundation, Ignasi Miró, the director of CaixaForum Madrid, Isabel Fuentes, and the head of Science exhibitions at the "la Caixa" Foundation, Javier Hidalgo, today presented Mammoth. The giant of the Ice Age, an exhibition that explores the life of these fascinating and mysterious animals, true icons of the Ice Age.

At a time when the world is trying to reconnect with mammoths, which became extinct four thousand years ago, CaixaForum Madrid is hosting this exhibition in which visitors can take an exciting journey back to the ice age without leaving the city, getting to know the mammoths up close and immersing themselves in their habitat.

The exhibition, produced by "la Caixa" Foundation, allows visitors to surround themselves with these mammals and understand how they lived, thanks to the exhibition of a real fossil of a woolly mammoth, originally from the Tyumen region (Russia). This impressive skeleton, 6 metres long and 3.5 metres high, which is between 40,000 and 50,000 years old, is the centrepiece of the exhibition. 

Mammoths belong to the proboscidean family, which includes animals with trunks, and their origins date back 60 million years. Of this family, 200 species have been identified, including the one that gave rise in Africa, 9 million years ago, to the elephant family, which today has only three species, of which the Asian elephant is the closest living relative to the mammoth.

The first mammoths appeared in Africa 5 million years ago, and a little over 3.5 million years ago they left Africa and continued their evolution in other parts of the world, as can be seen in some of the maps in the exhibition.

Woolly mammoths (Mammuthus primigenius) roamed over vast areas from the UK to Spain in the west and to Siberia, China and Japan in the east. They then passed through the icy Bering Strait to Alaska and from there to the Great Lakes region. About 4,000 years ago, the last mammoths disappeared in the Russian Arctic.

The woolly mammoth is the best known species of the Ice Age thanks to evidence, from fossilised skeletal remains to frozen mummies, that has allowed extraordinary studies, considering its age, DNA and lifestyle. Woolly mammoths were smaller than the species that preceded them ⸻southern mammoth and steppe mammoth⸻ and smaller than the next lineage, the Columbian mammoths of North America. 

The exhibition contains molar specimens from the Museo Nacional de Ciencias Naturales-CSIC and the Instituto Catalán de Paleontología Miquel Crusafont, which show how the dentition of the different genera of the proboscidean order, including several mammoth species, evolved.

The diet of the first proboscideans was based on leaves, bark and fruits found in wooded environments, for which they used their molars with rounded cusps. However, a change in the climate spread the grasslands and the ancestors of elephants saw their dentition change as they began to eat more grass, rich in fibre and silica, requiring molars with ridges that allowed them to grind it.

As a consequence of the changes in dentition, the shape of their jaws and associated muscles also changed, causing their heads to become shorter and taller than those of their ancestors. Also, as their body size increased, the tusks lengthened and the proboscis developed. 

In the case of mammoths, the different species of this genus also adapted to an increasingly grassy diet as their habitat changed due to cooling. This resulted in a greater number of ridges on their molars and increased crown heights to cope with the wear and tear of an increasingly abrasive diet. 

One of the most striking features of mammoth dentition is their defences (tusks), which grew from their base throughout the mammoth's life, adding dentine deposits. In the case of the first proboscideans, the fenders had a double layer. On the one hand, enamel, which was hard but tended to fragment, and on the other, dentine (ivory), which was more flexible but more resistant in fights. In the case of mammoths, whose fenders were much larger and more curved in males than in females, the tusks contained only dentine.

A section of a fender in the exhibit shows the growth rings of the mammoths. Analysing the isotopes of a mammoth's fender can reveal a lot of information about its life, such as its life cycle, changes in diet, pregnancy, oestrus, climatic changes or the cause of its death. 

The mammoths' fur also stands out, which, from various investigations of their DNA, it has been possible to find out that it was not uniform, but that there was a gradation from lighter to darker tones, with the orange colour being unrealistic, as it would have lost natural pigments after years of burial.

Mammoths had three types of hair that helped protect them from the cold. On the one hand, a fine hair of 5 centimetres prevented heat loss. Next, 15 to 30 centimetre hairs provided good insulation, and finally, there were thick, hollow hairs up to 90 centimetres long along the flanks and under the chin. In addition, sebaceous glands secreted a fluid that made the hair waterproof, and a thick layer of fat up to 10 centimetres thick gave them greater insulation.  

Based on what has been deduced from research on specimens preserved in permafrost, and combining this information with what we know about modern elephants, we have some insight into the life of mammoths. These mammals, accustomed to living gregariously with more than a dozen other individuals, consumed up to 180 kilos of grass per day and migrated south in winter.

During the rutting season, males secreted temporin, a strong-smelling liquid, through glands on both sides of their heads, and behaved more aggressively towards other males. Births, after 22 months of gestation, usually took place in spring.

The exhibition also reflects on the extinction of the mammoths, which is still shrouded in mystery between those who think it was human action and those who say that climate change caused their disappearance. Rising global temperatures favoured the spread of forests, eliminating large areas of grassland and thus depleting mammoth populations, which also suffered from poaching. Mammoths were an important source of protein, fat and fur. Their bones were also used to make tools and weapons, although the most sought-after were the ivory fenders, which were used to make sculptures and other objects. Their living relatives, elephants, face identical threats and it is up to us to ensure that they do not meet the same end.

Today, advances in the field of genetics are giving rise to several research projects that aim to revive mammoths from DNA obtained from well-preserved specimens, generating ethical debate about whether and for what purpose this should be done, beyond scientific progress.