The arrival of European settlers in Guadeloupe caused the extinction of 50% to 70% of the snake and lizard population in the archipelago, according to a study published on May 19, 2021. A total of 43,000 reptile fossils from six islands were studied for this work, published in the journal Advances in science.
Mass extinction in the last 500 years
“We have discovered that there has been immeasurable biodiversity in the past, with many species not known to be present until now, as well as those that have never been described before.“, the study’s lead author, Corentin Bochaton, of the CNRS and the Max-Planck Institute, told AFP. A team of researchers analyzed the remains of 16 groups of animals (taxa) with 31 sites in Guadeloupe. They were found classified into four periods: Upper Pleistocene (32,000 to 11,650 years ago), the Holocene before the arrival of humans (beginning 11,650 years ago), the native settlement and the modern period.By dating the bones and sediments around, scientists are reconstructing the evolutionary history of this region and found that mass extinction occurred in 500. The islands may have been first inhabited by humans as far back as 5,000 years ago.Christopher Columbus arrived in Guadeloupe in 1493, and French colonization began in 1635, leading to the extinction of the indigenous populations that lived there.According to the fossils studied, these species reptiles managed to survive climate change at the end of the last ice age, when the area became warmer and wetter.
Species that hunt animals brought by settlers
“We did not notice any extinction during the American period“, also explained Corentin Bochaton. So what led to the extinction of species such as the curved-tailed iguana or Marie-Galante’s limb? According to researchers, cats, mongooses, raccoons or rats brought by settlers are responsible. Small reptiles have apparently passed better than larger ones, which may indicate predator propensity.Tree-dwelling species also appear to be less affected – due to Corentin Bochaton’s consequence of the role of agriculture destroying land habitats.This research demonstrates the importance of using fossils to assess human impact to the region’s biodiversity.In Guadeloupe, the change was indeed so sudden and violent that naturalists did not have time to document the local fauna.