cichlids
(Reformed) New Scientist 12: Evolution favors some outcomes, not others
Female fish mate OUTSIDE their species?
Dollo’s Evolution Law gets hit again: Stripes come and go
From ScienceDaily: More than 1200 types of colourful cichlid can be found in the large African lakes Malawi, Victoria and Tanganjika. Not only are they very diverse in colours, they also have numerous colour patterns such as horizontal or vertical stripes. “But that’s not all” explains Axel Meyer, “cichlids are prime examples of evolution. They are extremely diverse in terms of social behaviour, body shape, colour pattern and many other biological aspects, but at the same time certain features repeatedly evolved independently in the different lakes.” This principle of repeated evolution — biologists term it convergent evolution — makes cichlids the perfect target to study the genetic basis of this phenomenon. If similar colours and body shapes have emerged in Read More ›
Claim: Hybridization “boosts evolution” in cichlids
From ScienceDaily: Animals that have either migrated to or been introduced in Central Europe — such as the Asian bush mosquito or the Asian ladybeetle — feel extremely comfortable in their new homes due to changing climatic conditions. If these newcomers are genetically compatible with local species, they may crossbreed and produce hybrids, which can continue to evolve under local environmental conditions — a process that has been shown to have taken place during human evolution, between Homo sapiens and Neanderthals for example. New genes contributed by foreign species provide new genetic combinations that can be beneficial and are thus favoured by natural selection. According to hybrid swarm theory, interbreeding between hybrid species and parent species may then lead to Read More ›