Spiny eels have confirmed that Lake Tanganyika is an evolutionary hotspot, according to a study by scientists from the UK and South Africa published in a recent issue of the journal BMC Evolutionary Biology.
The paper by Katherine Brown, Lukas Rüber, Roger Bills and Julia Day is the first molecular phylogenetic study of the spiny eels and focuses on the evolutionary history and biodiversity of the spiny eels from lake Tanganyika.
The authors used a dataset comprising 3118 base pairs of mitochondrial (Cytochrome b, Cytochrome c oxidase subunit 1) and nuclear (ribosomal S7 introns 1 and 2) gene sequences to examine the phylogeny of the spiny eels, with emphasis on the species found in Lake Tanganyika.
Based on their results, the authors concluded that the Lake Tanganyika spiny eels evolved into five different lineages from a single common ancestor, that colonised the lake about 7–8 million years ago.
The evolution of the different lineages within the Lake Tanganyika spiny eels was found to coincide with periods of lower lake level.
The colonisation and diversification of spiny eels in Lake Tanganyika so soon after its formation (estimated at 9–12 million years ago) supports the view of the lake as an evolutionary hotspot of diversification.
The authors also found evidence for undescribed diversity of lacustrine and riverine species of African spiny eels in their study.
In addition, their analyses also highlight a split of African and Asian spiny eels at about 19 Myr. This is considerably younger than the split between their associated continents, suggesting a dispersal scenario for their current distribution.
For more information, see the paper: Brown, KJ, L Rüber, R Bills and JJ Day (2010) Mastacembelid eels support Lake Tanganyika as an evolutionary hotspot of diversification. BMC Evolutionary Biology 10, 188.