The skeleton of a mammoth found frozen in Siberia and then transferred to the museum of St. Petersburg. A good deal of the flesh and skin is preserved in a dried state on the head, whilst the feet are still encased in the great leathery pads which hide the separate toes. Drawing from Lankester (1905).
Origins
Mammuthus primigenius is a close relative to modern day elephants and one of the several genera in the order Proboscida that are extinct today (Haynes 1991). These large and strong creatures disappeared from the face of the earth about 10,000 years ago (excluding the dwarfs found on Wrangler Island), placing their extinction in the late Pleistocene (Haynes 1991). Mammoths were widespread throughout the world; evidence suggests that they lived in northern Asia, North America, parts of Mexico, and Europe, with the remains of a baby mammoth found in Siberia (Haynes 1991).
Mammoths first appeared in sub-Saharan Africa during the middle Pliocene epoch (3 - 4 mya). By the end of the Pliocene and the beginning of the Pleistocene they were extinct in Africa and widespread in Eurasia (Haynes 1991). Some species of mammoths lived in southern regions and became progressively cold-adapted as they moved northward into Eurasia. They eventually moved eastward and southward into North America about 1.7 mya (Early Pleistocene). Mammuthus primigenius was part of the second wave of mammoths to migrate to North America, and these mammoths were relatively smaller than the older and larger wave of mammoths, one of which was Mammuthus columbi (Haynes 1991).
Physical Appearance
The head of the woolly mammoth was domed and slightly resembled that of the Asian Elephant of today. It was, however, more vertical as a result of adaptations of the jaw and teeth that assist in feeding on grass (Haynes 1991). The femur was the longest limb bone of the woolly mammoth, reaching a maximum of 1.2 meters (Adams Mammoth). Like all Elephantidae, the combined length of the humerus and ulna (fore-leg) was smaller than the combined length of the femur and tibia (rear-leg) (Haynes 1991). This could have evolved because it confers a feeding advantage, or it may have co-evolved with the large tusk. When compared to the African elephant, the size difference of the fore-leg and rear-leg was greater. They were also much smaller lengthwise (Haynes 1991). The reason for this difference in height is subject to debate, with some saying the woolly mammoth (being a grazer) would have to be lower to the ground in order to eat, while others say that the leg lengths had less to do with feeding and more with biomechanics of movement (Haynes 1991). Also, the diameter of the woolly mammoth’s femur was larger than that of elephants today.
The body profiles of mammoths and elephants were dissimilar due to both limb proportions and vertebral spine lengths. The spines on the woolly mammoth were small near the rear, and then increased abruptly toward the front, with the longest at the position of the front shoulder. The spine was also slanted backward and thus created a ‘hump’ that declined continually toward the rear of the mammoth (Haynes 1991).
Mammoths were predominately grazers, as dental and cranial adaptations for grass feeding were seen in fossil records, setting them apart from the rest of the Elephantidae. As expected, their teeth were large and blocky and had multiple enamel covered laminae (Haynes 1991).
The woolly mammoth was also entirely covered in a thick coat of hair (excluding the soles of its feet). The underfur grew to about 5-15cm while the longest straight hair grew to about a meter long. Even its trunk was covered in hair. The longest hairs grew on the tail and forelegs. The main function of the coat was to maintain body heat, especially after drinking water, since body heat was used to warm the water in the stomach. This would have been a great burden to the mammoth if not for its thick coat of hair (Haynes 1991). The hair of the 6-12 month old male mammoth carcass named Dima (discovered in 1970 by a bulldozer operator gold mining in Siberia) was redish brown. This gives a clue as to the color of the hair on mammoths, though whether this color changed later in life is not known (Haynes 1991). The sizes of the ears were relatively small compared to the African elephant of today. This would make sense as it would reduce the area from which heat could escape the body. Also, the African elephants often use their large ears to fan themselves, a function that would not be needed in the cold north (Haynes 1991).
The tusks of the woolly mammoth were much larger and denser than those of elephants today (Haynes 1991). There are a number of theories for this, some being that the mammoth had to use them to push away trees, or that they engaged in fighting a lot more that modern elephants. Wear patterns on the ends of the tusks suggested that they were used to push away ice and snow, possibly in order to expose grass (Haynes 1991). The tusks were also more curved and spirally. Since the tusks grew in spirals, the worn part of the tusk that was used to expose grass was quickly replaced by an unused portion of the tusk so as to continue efficiently moving snow. An adult male tusk length, including the curve, may reach as long as 3.5 m (Haynes 1991).
Sex and Mating
Like all Elephantidae, sexual dimorphism is observed within Mammuthus primigenius (Haynes 1991). The maximum shoulder height of males was approximately one meter higher than that of females. Overall males were much larger and heavier than females. They also had larger and heavier skulls as well as more massive tusks. When the fossils of mammoths from Siberia were examined, it was found that female tusks would grow lengthwise throughout life, but would decrease in circumferential growth at the age of sexual maturity (Haynes 1991). This is similar to the pattern observed in the African elephant of today, but it was not the case for the male mammoth, as the tusks would grow in length and circumference throughout life. When fossils were discovered in large groups, they were usually female, with male fossils being solitary. This would suggest a social order much like that of the elephants of today, with females and children herding together in large groups while the males were solitary and usually interacting with the females during the mating season (Haynes 1991).
Extinction
The reason for the woolly mammoth’s extinction has been a subject of debate for a long time. While some would say that the mammoth population was reduced due to overhunting, others claim that rapid climate change would have been the main reason for the decline of the woolly mammoth. Indeed, evidence in cave drawings show man hunting all types of creatures, the mammoth being one that was especially highlighted (Haynes 1991). The carcass of Dima had a hole in its side, some say from a hunters spear (Haynes 1991). However the woolly mammoth was adapted to cold climates, and as North America began to warm up and parts of the world began to defrost, the mammoths woolly hair would have created a coffin of heat. Another explanation presented acknowledged both arguments, stating that the change in climate reduced the habitat of the mammoth to a fraction, until human pressure by hunting was finally able to drive the species to extinction (Haynes 1991). The extinction of the mammoth is subject to wide debate and will probably be so for years, much like the extinction of the Neanderthal.
Interesting Facts
When mammoth bones were first discovered in the Americas, European explorers had thought of them as the remains of giants that lived before the biblical flood of Noah (Cohen 2002). A similar misconception first began with St. Augustine in book 15 of The City of God (5th century A. D.); he mistook elephant bones in North Africa for those of giants. The large and massive bones were then said to be those of giants in the pre-flood time, and claims were made that mankind was getting smaller and smaller as the centuries went by. Ironically it was not until the African slave trade that these bones were properly identified. The African slaves that were brought to the Americas were able to correctly identify the bones as coming from a large elephant-like creature (Silverberg 1970).
The cave drawings of the woolly mammoth show certain dissimilarities to the specimens recovered. In the drawings the mammoth’s rear is sloped very low compared to fossil records. Such a picture would suggest that the mammoth’s rear-legs are lower than its forelegs. Its head is also raised very high, as opposed to almost level to its back. These discrepancies may be due to the fact that pre-historic artists were more concerned about the front of the mammoth rather than its rear, and thus drew the dangerous end of the mammoth much higher and bigger than its rear.
