Anyone who does fieldwork knows that the work begins long before the wheels of the plane ever leave the ground. Before getting out there and getting those boots dusty, there’s a whole series of hurdles that must be cleared first: securing the correct permits, triple checking equipment, arranging supplies, confirming travel plans, and figuring out what to pack! (How many socks are enough? Is there such a thing as too many socks?)
I’m on my way to Nairobi, Kenya, to meet with Dr. Ellen Miller of Wake Forest University, one of the leaders or “principal investigators” of the Buluk Paleontological Research Project. We’ve spent the last couple months prepping for this field season, and I’m eager to get out there, see the site for the first time, and get to work. But preparation is key because once we leave Nairobi, we’re headed for Buluk, a remote site in East Turkana, Kenya, where we’ll stay for the next two months. While Buluk has been known as a fossil-bearing site since the 1970s, its location has made access difficult. There won’t be cell service, let alone internet, at our camp, but for the next two months I’ll be doing my best to send dispatches for this blog when I can.
Buluk is approximately 17 million years old (Ma), meaning it dates to the early part of the Miocene epoch. The Early Miocene (23 to 15 Ma) was an exciting time in primate evolution! Apes and Old World monkeys (a group called “Catarrhini”) had recently diverged from their common ancestor, and early members of these groups lived alongside more primitive catarrhines in diverse primate communities. Today, Old World monkeys are much more diverse and widespread than apes. If you try, you can probably name all the living apes without much difficulty, but listing all the living Old World monkeys would be a much more impressive party trick! During the Miocene, the tables were turned, and apes were so diverse that to name them all would be considerably more difficult than it is today. These Miocene apes varied in their size, diet, and locomotor adaptations, and there is plenty of debate today over which species are more closely related to the living apes. (For an interesting read about Miocene ape evolution, check out Dr. David Begun’s book The Real Planet of the Apes.)
By comparison, fossils of Old World monkeys are rare for most of the Miocene, and we know much less about their variation during this epoch. Buluk has already played a role in improving this sparse record for monkeys. In addition to fossils of an early ape and a small primitive catarrhine, Buluk has yielded some of the earliest Old World monkey fossils.
We hope that continued fieldwork here will help us understand more about these early apes and monkeys and give us a glimpse into the environments and broader faunal communities in which they lived. The mammals from Buluk tell the story of interchange between Africa and Eurasia. While the African continent had previously been isolated, Late Oligocene (approximately 27 to 24 Ma) contact between the Afro-Arabian and Eurasian plates allowed cross-continental exchange of animals. These new immigrants from Eurasia included the early relatives of many iconic African animals such as lions, rhinos, and antelope. At Buluk, some of these new arrivals existed alongside more archaic African animals like hyraxes, elephants, and an extinct group of carnivores called creodonts.
Fieldwork provides the raw material for improving our understanding of primate evolutionary history. The only way to learn about variation in the adaptations of early monkeys and apes is to find more fossils. Fossils from Buluk have already contributed to our knowledge of both the appearance and distribution of these animals, and we’re hoping this field season will continue to improve the Early Miocene fossil record. But first, I have to pack my socks.
(All photographs courtesy of Dr. Ellen Miller)