Are these Alcedo volcano giant tortoises a subspecies or a distinct species? Tui De Roy/Minden/naturepl.com
The number of species of Galapagos giant tortoises that exist is in dispute and the result could influence how we conserve these endangered animals.
Researchers have defined 16 populations of giant tortoises (Chelonoidis spp.) spread across the Galapagos islands based on differences in their shell shape, behaviour and genetics. Three of these are now extinct because of hunting, the loss of their habitat for agriculture and the introduction of invasive species, such as goats, which compete for their food. …
