Biological Sciences’ Daza Co-Authors Revealing New Study Linking Ancient African and South American Lizard Life

Dr. Juan Daza, of SHSU’s Department of Biological Sciences, is co-author of a new study that has discovered a new species of fossil lizard from Morocco that illustrates a link between African and South American life from 90 million years ago.

The study has been published in the journal Royal Society Open Science (an open access journal from the Royal Society of London).

escena-lagarto3-webDr. Daza and his fellow authors demonstrate the link between the new species, called Jeddaherdan aleodonta [see artist's conception at right], and New World iguanians (one of the most diverse lineages of contemporary reptiles, originating in the time of the dinosaurs, the Mesozoic Era). They note that Jeddaherdan fossils were found in rocks in Morocco that are dated between 100 and 90 million years old, meaning that the species was contemporaneous with well-known reptiles from that region.

Prior to the recent discovery, there were no previous records of iguanians from the Mesozoic of Africa. Jeddaherdan is an acrodontan lizard, constituting the first iguanian from the Mesozoic of Africa, thus being the oldest known iguanian from that continent--40 million years older than the previous oldest acrodontan record from Africa.

Jeddaherdan is of a similar age, and has a number of similarities, to a recently discovered lizard species from Brazil. This indicates important similarities between African and South American faunas at 90 million years ago. That was a crucial time in the history of the planet, with the opening of the Atlantic Ocean taking place and separating Africa and South America. Since then, lizard faunas in Africa and South America followed quite distinct evolutionary paths. Jeddaherdan is the first hard evidence that lizard faunas between both continents were still very similar during the separation of Africa and South America.

As Dr. Daza notes, “Looking at these lizards from the past tell us a lot about their history. Jeddaherdan has unique dentition, something that we cannot find in any close relative today; Its unique dental morphology makes me wonder about its dietary or tropic specialization, an aspect of its biology that we might never be able to know with certainty.”

The study was the result of an international team of collaborators, including lead author Sebastián Apesteguía (Argentina), Juan Diego Daza (Colombia), Tiago Simões (Canada), and Jean-Claude Rage (France).