WOOLLY RHINOCEROS: CHARACTERISTICS, HABITAT, CAUSES EXTINCTION - BIOLOGY - 2024

The woolly rhinoceros (Coelodonta antiquitatis) is an extinct species of rhinoceros that inhabited much of Europe and Asia during the last ice age. Along with other extinct species of rhinoceros and the current species they are part of the order Perissodactyla and the family Rinocerontidae. It was described by Blumenbach in 1799, being Coelodonta antiquitatis the type species of the genus and the most recent in the time scale.

When they were discovered, the researchers could not believe that rhinos existed that lived in conditions with such low temperatures and, from this, many hypotheses emerged (which were later refuted) to explain their presence in these areas.

Reconstruction of the Woolly Rhinoceros (Coelodonta antiquitatis) By UДиБгд

The woolly rhinoceros is part of a group of large mammals known as mammals of the mammoth steppe or "Mammuthus-Coelodonta" faunal complex. C. antiquitatis was the second largest mammal after the mammoth in northern Eurasia.

These animals are very well represented in cave painting as well as other Pleistocene mammalian species, which is why they are considered typical elements of the megafauna of this period.

Because few animals have been discovered with preserved soft tissues, information concerning their biology is scarce and much of the information reported is based on analogies with living rhino species.

The fur that covered them was abundant and brown in color. The feeding behavior is very similar to that of current rhinos and this evidence is supported by paleo-climatic reconstructions, pollen analysis and biometric models made from the skull.

The extinction of this mammal in Europe coincides with a widespread low temperature event known as "ancient dryas". Although other authors indicate that the disappearance is due to the expansion of forests as a result of climate change. On the other hand, the extinction of the last populations in Siberia is attributed to a warming period known as Bølling-Allerød.

General characteristics

They were large, robust-bodied animals, even larger than white rhinos.

It had short limbs and abundant fur or wool, as well as a thick skin that insulated it thermally to survive in tundra and steppe environments characteristic of high latitude regions during the Pleistocene ice ages.

The total length of these large mammals ranged from 3.5 to 3.8 meters in males and from 3.2 to 3.6 meters in females, with a height that could reach two meters and 1.6 meters at shoulder level. The weight of these animals was greater than three tons in males and about two tons in females.

In contrast to today's rhinos, the woolly rhino's ears were narrower and the tail considerably shorter. These characteristics reflect Allen's ecological rule as an adaptation to cold weather.

The upper lip is short and wide similar to that of the white rhinoceros, being an additional indication of its diet based on grasses and cereals. In the following video you can see how this species could be:

Horns characteristics

Like today's rhinos, the horns of woolly rhinos are made up of filaments or keratinized lamellar fibers arranged in parallel along the longitudinal axis. These fibers are packaged within a melanized amorphous matrix of polyphasekeratin.

Palynological analyzes have determined the presence of various species of grasses, Artemisia, Betula, Alnus, ferns and mosses.

Seasonal variation in diet

Like the woolly mammoth, C. antiquitatis probably fed on grasses and sedges for most of the year. However, as it is not a migratory animal, it is possible that during the snowy and rainy season its diet will vary.

Stable isotope analysis in the horns, together with those present in the frozen soil (permafrost) around the fossils, reveal that the differences in the composition of the cartilaginous tissue layers of the horn are mainly due to a seasonal change in diet. This also occurs with the horns of some modern mammals.

The dark and less dense areas of the horn are associated with a diet based on herbs and superficial grasses given the positive content of C ₁₃ and N ₁₅, coinciding with the typical summer feeding. On the other hand, the lighter and less dense areas are associated with feeding from herbaceous and woody plants during winter.

Reproduction

This species had a great sexual dimorphism superior to that of living species. The horns of the males were quite developed, which is why it is believed they had an attraction function on the females in addition to using them in the fights against other males and as a defensive measure against predators.

It is likely that the reproductive characteristics were similar to those of today's rhinos. These animals had low reproductive rates. The discovery of well-preserved females with a two-teat udder indicates that a female probably only gave birth to one calf and exceptionally two.

By analogy with current rhino species, it is indicated that a female could become pregnant every two or three years or even more. It is not known if there was a specific breeding season throughout the year, as most of the finds of woolly rhinos or large well-preserved parts belong to females.

Behavior and interactions

It is possible that, due to the size and shape of the horn of these rhinos, in times of low temperatures and low food availability these animals used their huge horns to dig in the snow and expose the vegetation on which they fed.

It is known from indirect data, as well as the presence of other mammals, that the layers of snow that formed in the habitats of these animals did not exceed 30 cm, which favored their movement between them.

Those habitats that presented more abundant snow constituted an impediment to the mobility of these animals and probably prevented their dispersal to the American continent.

The existence of woolly rhinoceros skulls with some minor and severe trauma indicates that these animals have very likely been strongly territorial.

As is the case with rhinos today, fighting between rhinos used to be frequent and in rare cases resulted in serious injuries to the skull. Perhaps, due to changes in the availability of resources in winter, the relationships between individuals increased in aggressiveness, as a result of intraspecific competition.

References

1. Boeskorov, GG (2012). Some specific morphological and ecological features of the fossil woolly rhinoceros (Coelodonta antiquitatis Blumenbach 1799). Biology bulletin, 39 (8), 692-707.
2. Deng, T., Wang, X., Fortelius, M., Li, Q., Wang, Y., Tseng, ZJ,… & Xie, G. (2011). Out of Tibet: Pliocene woolly rhino suggests high-plateau origin of Ice Age megaherbivores. Science, 333 (6047), 1285-1288.
3. Fortelius, M. (1983). The morphology and paleobiological significance of the horns of Coelodonta antiquitatis (Mammalia: Rhinocerotidae). Journal of Vertebrate Paleontology, 3 (2), 125-135.
4. Garutt, N. (1997). Traumatic skull damages in the woolly rhinoceros, Coelodonta antiquitatis Blumenbach, 1799. Cranium, 14 (1), 37-46.
5. Jacobi, RM, Rose, J., MacLeod, A., & Higham, TF (2009). Revised radiocarbon ages on woolly rhinoceros (Coelodonta antiquitatis) from western central Scotland: significance for timing the extinction of woolly rhinoceros in Britain and the onset of the LGM in central Scotland. Quaternary Science Reviews, 28 (25-26), 2551-2556.
6. Kuzmin, YV (2010). Extinction of the woolly mammoth (Mammuthus primigenius) and woolly rhinoceros (Coelodonta antiquitatis) in Eurasia: review of chronological and environmental issues. Boreas, 39 (2), 247-261.
7. Stuart, AJ, & Lister, AM (2012). Extinction chronology of the woolly rhinoceros Coelodonta antiquitatis in the context of late Quaternary megafaunal extinctions in northern Eurasia. Quaternary Science Reviews, 51, 1-17.
8. Tiunov, AV, & Kirillova, IV (2010). Stable isotope (13C / 12C and 15N / 14N) composition of the woolly rhinoceros Coelodonta antiquitatis horn suggests seasonal changes in the diet. Rapid Communications in Mass Spectrometry, 24 (21), 3146-3150.