Kenya fossils solve ancient monkey mystery

A fossil of a newly discovered species of monkey living in Africa 22 million years ago is a "missing link" in the evolution of primates, according to scientists.

The extinct monkey fossil was found in the badlands of northwestern Kenya and was first confused with a pig because the specimen was so primitive.

Scientists say that the teeth, of the Alophia metios species, help fill a six million year deficit in the fossil record.

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Prof. Ellen Miller of Wake Forest University in Winston-Salem, North Carolina, explained, "These teeth are so primitive when we first showed them to other scientists, they told us : "Oh no, it's not a monkey. It's a pig.

"But because of other dental features, we are able to convince them that yes, it's actually a monkey."

The newly identified monkey teeth are more primitive than the geologically younger fossils.

This suggests that he has lived the "good life" by taking advantage of the wide variety of fruits, seeds and nuts growing in the rich forest.

They miss what the researchers mentioned a pair of molar ridges called "lophs" that owes its name to Alophia – which means "without lophs".

This sheds light on the mystery of expanding the reach of prehistoric monkeys across the Old World.

The teeth of Alophia metios were found in exposed rocks in the eroded desert badlands of northwestern Kenya near Lake Turkana.

Crucially, they have been dated exactly between 19 and 25 million years ago from fossilized monkey teeth found in Uganda and Tanzania, respectively.

This last one would have belonged to the first monkey of the world.

The study published in Proceedings of the National Academy of Sciences also suggests that the evolution of their evolution has been altered by their diet.

Professor John Kappelman, a correspondent at the University of Texas at Austin, said, "For a group as powerful as the apes of Africa and Asia, it would seem that scientists would have already understood their evolutionary history.

"Although the isolated tooth of Tanzania is important for documenting the earliest appearance of monkeys, the 6 million years after the creation of the group are white.

"This new monkey significantly reveals what happened during the subsequent evolution of the group."

The interval is represented by only a few African fossil sites. Anthropologists have therefore targeted the wealthy region of Western Turkana in an attempt to fill the void.

Benson Kyongo, head of collections at the National Museum of Kenya in Nairobi, said: "Today, this region is very arid.

"But millions of years ago, it was a landscape of forests and forests crisscrossed by rivers and streams. These ancient monkeys lived a good life.

The expedition uncovered hundreds of jaws, limbs and teeth belonging to an assortment of mammals and reptiles that roamed the Earth 21 to 24 million years ago. These even included the remains of the first elephants.

The success of the Old World monkeys seems to be closely related to their unique dentition, the researchers said.

Today, the configuration of cusps and lophs on molars allows them to process the wide range of plant and animal foods encountered in the diverse environments of Africa and Asia.

Mercedes Gutierrez, a professor of anatomy at the University of Minnesota, said, "You can think of the modern monkey molar as the only food processor that can slice, dice, chop, and chop. crush all kinds of foods.

Monkeys are omnivorous – which means that they eat meat and plant-based foods. Most eat nuts, fruits, seeds and flowers. Some also eat bird eggs, small lizards, insects and spiders.

Professor James Rossie, of Stony Brook University in New York, said, "How and when this unique dentition has evolved is one of the unanswered questions in the evolution of primates."

Researchers believe that Alophia's teeth were adapted to a diet consisting of hard fruits, seeds and nuts – not leaves.

These are more effectively treated by the more evolved dentition of fossil apes dating back to 19 million years ago.

Samuel Muteti, a researcher at the National Museums of Kenya, said: "It is generally assumed that the trait responsible for the success of a group has evolved from its inception.

"But Alophia shows us that this is not the case for the monkeys of the Old World. Instead, the characteristic dentition of modern monkeys evolved long after the first appearance of the group. & # 39;

Researchers believe that the inclusion of leaves in the diet is what later led to the dental evolution of the monkeys.

The monkeys were born at a time when Africa and Arabia formed an island continent.

His animals evolved in isolation until the land mass joined Eurasia between 20 and 24 million years ago.

It is only after this that today's mammals are generally considered "Africans" – antelopes, pigs, lions, rhinos, etc. – have entered the continent.

Researchers question whether this event and the possible competition between residents and newly arrived Eurasian species led the monkeys to exploit the leaves.

On the other hand, the change of climate could have made the leaves more attractive in their menu.

Professor Kappelman said, "The way to test between these hypotheses is to collect more fossils.

"Establishing when exactly the Eurasian fauna entered Africa remains one of the most important issues of paleontology.

"Western Turkana is one of the only places where we know this answer." His team plans to come back later this year to find more answers. & # 39;