The Tree Of Life

The evolution of humans and primates in Asian

- YD Bar-Ness

OUT ON A LIMB

This is a story about our little branch on the tree of life. Let us journey out on a figurative limb, balancing our way along the branch we share with the primates, and then onto the smaller branch we call Homo. Thanks to advances in genetic technology, working in tandem with fragments of fossil evidence, we are starting to get a sense of where, geographically, this strand began.

The “tree of life” is a conceptual illustration of the interrelatedness of life, similar to the concept of the family tree, but grander in scale. This scientific endeavour is known as “taxonomy”, derived from two Greek words: taxis, which means order or arrangement, and nomos, which means law or science. Together, they form the branches of this elaborate tree structure.

In taxonomy, every group has a sister group – its closest relative. You could think of the sister group as the neighbouring branch. The branching point is their last common ancestor. We share a relatively recent common ancestor with apes and monkeys, a less recent ancestor with all mammals, and a distant ancestor with all other animals. If you journey into the past, you will find that all living organisms share a common ancestor.

Let’s see where humans are situated on this tree, and examine the research that seeks to determine when, and from where, these branches evolved. Where on Earth did modern humans evolve? Where did apes come into being? Who is our closest relative? To place any organism on the tree of life, there are three main lines of scientific inquiry: living anatomy, fossil anatomy, and genetic research.

COMPARATIVE ANATOMY