Many people do not realize that evolution is not linear. The traditional image of evolution is still depicted by that poster hanging on the wall of the grade school science classroom that shows some of our ancestors in a line, starting with a crouching ape then progressing to a fully standing human. A Neanderthal is in the line as well as numerous other more ape-like ancestors. This poster gives the impression that evolution is linear, but that impression is incorrect.
Evolution is a series of adaptations, and would be more correctly depicted as a complex tree with many branches and sub-branches. The fact that evolution is not linear is the reason why monkeys and apes still exist. We are more like cousins of apes rather than a more highly adapted version of them. But we’re not just cousins of apes. We’re also cousins with all vertebrates and we all have common ancestry. Now, a fish that has a human-like face is being called a missing link by scientists.
Scientists are continually finding missing links in the evolutionary tree, and have recently uncovered an enormously exciting fossil that is 419 million years old. Scientists say it is a missing link because it answers questions about the evolution of all jawed vertebrates (including us.) This fish, named Entelognathus, which translates to “complete jaw,” has “the same basic configuration seen in our own human skulls.” Its significance in the world of biologists and palaeontogists cannot be overstated. Lead study investigator Zhu Min, who is a scientist at the Institute of Vertebrate Palaeontology and Palaeoanthropology explained, “Wow, it is beyond our wildest expectation if we stick to the available phylogenetic scenario. But the fossils provide evidence to force us to have reconsideration on the hypothesis… In this case, our distant ancestors didn’t develop their bony skeletons from scratch; they simply inherited them from their armored ancestors.”
Oxford Paleobiologist Matt Friedman says we share much in common with our aquatic ancestors. When people think of our evolutionary ancestors, they generally think of apes, but Friedman says, “We’ve got bony plates too. We’re a special kind of bony fish that’s gone onto land and lost its fins.”
He went on to explain:
This is an unexpected discovery that inverts schoolbook teaching on the evolution of bony skulls. Up until now it had been thought that the anatomical peculiarities of bony fishes – the group that would eventually give rise to human beings – are specializations that arose later in vertebrate evolutionary history in our own bony fish lineage. But now that narrative has been turned on its head.
How much time have you spent, up until now, thinking about your bony fish lineage? Should we be commissioning artists to paint huge portraits of our bony fish ancestors to hang on our walls? Apparently, these fishy friends have a lot more to do with our evolution than we thought.
Evolution is not linear, and now, a fish with a human-like jaw and face has been discovered. Hopefully, that evolution poster will start to change soon to better depict our watery roots.
By: Rebecca Savastio