The Great Speciator

I have been keeping exotic species of animal all my life. At the age of six, as a small boy living in what was then the British Crown Colony of Hong Kong, I had my first zoological collection - a large praying mantis, (Tenodera sp) and some caterpillars which eventually hatched out into a small hawkmoth species, most probably (Macroglossum stellatarum) the hummingbird hawkmoth.

My zoo resided in two large glass pickle jars on the bathroom windowsill, and over the next few years it expanded dramatically.

Eventually I had quite a sizeable collection of birds of the air and beasts of the field, and by the time I was nine my tastes in wildlife had been solidified, and my animal collection would have seemed quite familiar to anyone who frequents the CFZ forty years later, in the first decade of the 21st Century.

Amongster the animal groups which I started keeping (and which I still keep today) were various softbills - “birds with relatively soft bills, which feed upon invertebrates and soft plant material and whose young are helpless at birth”. Amongst these were various babblers (see my post of a few days back) and a pair of white eyes.

These are small khaki-ish green birds with white feathers around their eyes. About the size of a robin, they are wonderful little creatures with great personalities (unusual in a flocking bird), but it was only today that I learned something particularly unique about them. form new species faster than any other known bird, according to a University of Kansas (KU) researcher who used modern genetic techniques to answer an 80-year-old question about how fast new bird species can form.

Some island-dwelling white-eyes have long been dubbed "great speciators" for their apparent ability to rapidly form new species across geographies where other birds show little or no diversification, said Rob Moyle, ornithology curator at KU's Biodiversity Institute and an author of a study of white-eyes.Moyle, along with Chris Filardi of the American Museum of Natural History; Catherine Smith of the University of Washington; and Jared Diamond of the University of California-Los Angeles, has been able to reconstruct key aspects of these birds' evolutionary history using genetic analyses.

The authors used DNA sequences and a variety of analytical methods to determine that most of the family speciated at rates among the fastest of any known vertebrate.More than 100 species in the familyMore than 100 species in the family have spread across vast regions from Asia to Africa and to far-flung islands. Despite this ability to disperse over long distances, some species remain separated by water gaps as narrow as 2.2 kilometres and yet show no inclination to cross. "As we started to compile the data, we were shocked," said Moyle. "White-eye species from across the family's range had strikingly similar gene sequences, indicating a recent origin and incredibly rapid diversification".

The authors of the study, published in the prominent journal Proceedings of the National Academy of Sciences, assert that traits of white-eyes may have helped them diversify. These include sociability and the ability to survive in a variety of habitats. Some species also may have become more sedentary and unwilling to cross narrow water gaps.