Image 1: Darwinius masillae in its fossilised form.
The finding of fossil Ida scientifically known as Darwinius masillae was a mind changer to everyone studying palaeoanthropology. She was named ‘Darwinius’ to commemorate the 200th birth anniversary of Charles Darwin who was the pioneer of the study of evolution. What is now considered the anthropological equivalent of the ‘holy grail’, she was found 20 years ago although the exact unearthing of the fossil is not clear from Messel pit, near Frankfurt in Germany. It was stored in position of a private collector as artwork mounted on his wall, which was later traded for a million U.S. dollars to a Norwegian vertebrate palaeontologist Jørn Hurum. Jørn named the fossil Ida after his daughter. She was studied by Hurum and his team in secrecy for two years before she was revealed to the world.
It is the most comprehensive fossil primate ever found mainly due to the preserving factors when Ida died. It was believed that 47 million years ago the Messel pit was an enormous volcanic lake surrounded by jungles. It is thought that during that time every now and then a layer of carbon dioxide would form on the water surface, asphyxiating the animals coming to drink water. The animals would then pass out and fall into the water and drop to the bottom. The lake being volcanic was rich in minerals, hence low in micro-organisms decomposing the remains which facilitated fine preservation of fossils. In fact the preservation was so good that the fossil was found 95% complete, including individual hair and fur and her last meal which included fruits and leaves.
Ida’s anatomy was quite simple. Ida was a female roughly nine years old when she died, evidenced by skeletal structure (lack of baculum as seen only in males) proving it was a female and the presence of milk teeth along with hidden teeth right up in the jaw which haven’t merged yet indicates her age. The shape of her teeth also suggests her diet which consisted of leaves, seeds and fruit as seen by jagged molars enabling her to slice food. This along with the fruits and leaves found in her stomach confirms the theory. She was about 58cm or 23 inches long from head to tail. Ida had large eye sockets as she was a nocturnal. Her relatively short limbs suggest she was a tree climber. Her right wrist bone or right metacarpals fused to form a risen lump, indicating that she broke her wrist at an early age, feasibly caused by falling off a tree although her bone had thoroughly healed. This might have had a great impact on her tree climbing abilities and it is believed that she maybe searching the lands to forage fallen fruits. The age of Ida is dated to 47 million years, belonging to the second part of the Cenazoic epoch, the Eocene epoch which was followed by the Palaeocene. The Eocene period is treated with great importance due to the various fossils found during this period, many of which were found at the Messel pit.
Both monkeys and lemurs belong to the primate family. Lemurs have long tapering faces, a lean body and a long bushy tail. They have five digits in each limb along with opposable thumbs; however their grasps are not very firm. They have a toothcomb (a set of fused teeth in the lower jaws) and a grooming claw on their limbs. Monkeys on the other hand have a firm grip with the help of their opposable thumb and like humans have binocular vision. Monkeys lack a toothcomb and a grooming claw. Ida was considered as the missing link because she had features present in both monkeys and lemurs
Ida’s fingers and toes were long; she had an opposable thumb and rounded fingertips with nails instead of claws. Surprisingly she had many more teeth compared to an average primate. Taxonomists try distinguishing fossils based on whether the nose of the fossil was wet or dry and classify the two types as prosimians and anthorpoids. Ida shows characteristics of both which makes her find even more
