Evolutionary Chain


The concept of evolution refers to the change of condition that gives rise to a new form of a particular object of study or analysis. It is important to note that evolutions are gradual processes, changes that occur gradually and can only be observed through the passage of time.

The short individual with great muscular strength, powerful jaws, long arms and a small brain that has just been rescued from the mists of time – and that anthropologists named Australopithecus garhi – adds a new link to the evolutionary chain that leads to the human being. .

“You cannot speak of a single link, because the transformation takes place very slowly,” explains Dr. Marta Méndez, a researcher at Conicet and the anthropology section of the Museum of Natural Sciences of La Plata, but it is an important finding. that helps to complete the phylogenetic tree of the human being. »

According to the theory elaborated by Charles Darwin, thousands of generations in continuous evolution link the human being with his remote ancestor, the monkey. Between both ends of the road, the scientists identified several stations that express the mutations that led to the current reality.

Australopithecines were the first primates to walk upright and with their hands free. “For a long time, scientists debated whether they were our ancestors or cousins,” write Johanson and Edey in “The Early Ancestors of Man.”

But, according to the collected evidence, it is assumed that human evolution began from a primitive type, similar to anthropoid apes, which gradually transformed over millions of years. Surely, the scientists affirm, there was not a sudden jump from the anthropoid to the man, but a blurred era of intermediate types that it would be difficult to classify in one or another group.

According to Dr. Méndez, the discovery by the team led by Tim White and Berhane Asfaw that was published in the latest issue of the journal Science is remarkable. “We have to keep in mind that, due to the time that has passed, the preservation of these types of fossils is very problematic,” he says. “The three findings, one of which is an antelope with remains that seem to have been treated by humans, if their contemporaneity is proven, could show that there would have been hominin intervention at that time,” says Méndez.

But it also makes clear that, beyond the brilliance of the discovery, there is still a lot of work to be done to clear up a number of dark spots. “The group of researchers will have to continue working, they will have to present their results at conferences and submit them for discussion with their peers, a journey like this never ends in a publication.”

Among other things, it will be necessary to examine not only the macroscopic characters, but also the microscopic ones, and to expose the samples to the meticulous examination of molecular biology.

“You have to work with old DNA, with special techniques that require extreme care, because contamination is very frequent,” says Méndez. “There are still a lot of potholes to fill. But this team will surprise us with new findings in the future.”