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There are 3 comments on Birds of a Feather

  1. Good work! It seems to me that you can’t have species interbreeding to form new species if, by definition, different species can’t (or don’t) interbreed. So yes, you really do need to make up your minds what constitutes a species. Also, you are pointing to speciation as a means of evolution. If this is true, how could a bird – in lay parlance – ever evolutionarily become something other than a bird of a different feather, so to speak, or could it? Consider that you’re saying speciation is how we humans got here. Thanks for allowing me to comment.

    1. Thanks for the comment!

      “…if, by definition, different species can’t or don’t interbreed…” – this definition of species comes from Mayr’s biological species concept, which emphasizes reproductive isolation, but this study on finches and many other studies on a variety of organisms challenge this definition of species and suggest that the history of speciation is not always a simple bifurcating tree. It many cases, that history may look more like a web, in which diverging populations come back into contact and exchange genes through infrequent hybridization. Population genetics theory shows that natural selection can maintain the phenotypic differences between populations as long as hybridization is not too frequent. Studies like this suggest that the “general lineage concept” which asks whether different populations are on independent evolutionary trajectories may be a more useful concept/definition of species – in effect, there are species with “fuzzy boundaries.” Note that there are a number of recent studies showing that many modern humans carry a small amount of neanderthal DNA resulting from interbreeding following the migration of modern humans from Africa to Europe.

      As for the second question of what begets what (if I’m understanding correctly), of course humans did not evolve from birds or vice versa, but humans (along with other hominids described by paleontologists), chimpanzees, gorillas and orangutans all evolved from a common great ape ancestor. That process required several splits of the original ancestral lineage (i.e., speciation events) in order for the unique forms of the great apes to evolve. Finally, it is also true that both birds and mammals (along with reptiles and amphibians) trace their ancestry back to an early tetrapod vertebrate at ~400 million years ago.

  2. http://sciencerefutesevolution.blogspot.fi/2018/01/epigenetics-reasons-why-organisms-can.html

    Previous studies regarding rapid adaptations of Finches have already revealed several epigenetic mechanisms behind these adaptations. I wonder why your study doesn’t even mention these mechanisms that serious scientists know to contribute to the rapid ecological adaptation of these birds. Even a layman knows that diet is the most significant factor that induces gene expression. Other strong contributors are climate, stress factors, sensory stimuli, pheromones etc. We also know that alterations in epigenetic information layers trigger genetic errors. Considering previous research on Galapagos Finches, some SNPs and CNVs were reported. It’s the same with human DNA. But do you know that modern scientists are willing to develop techniques by which they could repair most of human SNPs?

    http://sciencerefutesevolution.blogspot.fi/2018/02/scientists-to-realize-that-mutations.html

    I have to say your research is far away from modern understanding of why ecological adaptation occurs and what it results in.

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