【化石】古代の気候変動後もカリブ諸島で長く生き続けたコウモリ

A major change in climate after the end of the last ice age was not the primary cause of extinction of Caribbean bats, a study in Scientific Reports indicates. It was thought that reductions in land area and changes in climate and habitat associated with the late Pleistocene/Holocene (glacial-interglacial) transition, which took place about 9,000-11,000 years ago, led to losses in bat populations. However, a combined analysis of bat fossils and climate models reveals that some species withstood the changes during this transition and persisted for around 5,000-7,000 years after this period.

The Caribbean islands have experienced substantial mammal extinctions since the end of the last ice age. The loss of some mammals, such as primates, rodents and sloths, has been linked to the arrival of humans around 7,000-8,000 years ago, whereas the loss of bats has been attributed to environmental changes that occurred during the Pleistocene/Holocene transition.

A new analysis of radiocarbon-dated bat fossils from the Bahamas, performed by J. Angel Soto-Centeno and David Steadman, provides evidence that suggests losses of bat populations occurred much later, around 4,000 years ago. These findings imply that the cause of bat population loss in the Caribbean is more complex than previously thought. More comprehensive analyses of the extinction timeline for Caribbean bats are needed to gain a better understanding about when populations and species were lost, the authors conclude.