Spot the Difference
What you see isn’t always the truth. A revelation on the identity of species.
A species seems to most something fairly easy to describe, even young children are taught how to identify between different species of animal in their picture books. In life science however "What is a species" is actually a subject of contention. A quick search yields at least 11 different definitions of the word but all share the common idea that a group of organisms capable of reproducing are a species. Hybrids, infertile offspring and ring species are a few examples of where this causes contention.
It is actually of huge scientific importance to be able to correctly identify animals as members of different species. In the Galapagos archipelago, there have been attempts to revive extinct species of giant land tortoise through selective breeding of the most genetically similar extant relatives within other species. In the Canary Islands just this year the blue chaffinch was revealed not to be comprised of two diverging sub-species but of two genetically distinct species (F. polatzeki and F. teydea). Through integrative taxonomy, researchers were able to identify the Gran Canaria population as its own species which subsequently became Europe’s rarest songbird species. Conservation efforts benefit then from the knowledge of species differentiating from one another as the Gran Canarian species, F. polatzeki will now be granted different IUCN status to the previously larger population it was thought to belong to.
Why is this an important topic to bring up now, and what other ways can species identification benefit life scientists or possibly even provide further barrier to their work? Unbelievably, as studies claim many larger land mammals thought to be easily identified and studied behaviourally as our knowledge of them extends further back than most species historically, the giraffe of all animals (a recent study in Current Biology claims) is actually a term used to describe a collective of four distinct species. Fennessy et al. performed multi-locus genetic analyses on 190 individuals from across the previously clustered 9 sub-species and claim to have identified 4 distinct genetic clusters within the ‘giraffes’. Given the names: Southern giraffe (in South Africa, Namibia and Botswana), Masai giraffe (Tanzania, Kenya and Zambia), Northern giraffe (central and eastern Africa) and the Reticulated giraffe (Kenya, Somalia and Ethiopia), the genetic studies are backed up by common visual differences in the species also.
Axel Janke of the Current Biology study explores the implications for conservation, with under 10,000 individuals comprising each species’ population, all species should be afforded specific conservation efforts and goals. Whether the ecology of each species is significantly different from the others is something the researchers feel should be given further light, with Janke stating “no one really knows, because this megafauna has been largely overlooked by science”. This study could have implications for the further study of other charismatic megafauna that has been overlooked with the intent on understanding them better on a genetic level. The impacts will undoubtedly also be felt in zoos with captive giraffe breeding programmes, although the role of zoos in conservation is best saved for a whole other day of blogging.
Let us at Farsight Conservation know what you think the future effects of species divergence discoveries might be on our blog, or at our Twitter, Facebook and Tumblr pages.