I hesitate to single out colleagues for what is attributed to them in the media, because often what one says in an interview is not entirely what appears in print. On the other hand, I have noticed a tendency for some genome researchers to demonstrate a number of misconceptions about evolution that I think should be identified so that 1) they stop misinforming the public, and 2) they don't let misunderstandings complicate their interepretation of data.
I commented on the old Genomicron about some examples by Francis Collins with reference to non-coding DNA, in which he said:
I've stopped using the term ['junk']. Think about it the way you think about stuff you keep in your basement. Stuff you might need some time. Go down, rummage around, pull it out if you might need it. (Wired)
and
It is not the sort of clutter that you get rid of without consequences because you might need it. Evolution may need it. (Reuters)
I often have to remind students that evolution does not work this way, and that something is not kept because it might someday become useful.
The recent publication of the platypus sequence has brought out more examples that should not stand sans comment. For example, this by Jenny Graves of the Australian National University,
The platypus is a very ancient offshoot of the mammal tree, so it was 166 million years ago that we last shared a common ancestor with platypuses, and that puts them somewhere between mammals and reptiles, because they still maintain quite a lot of reptilian characteristics that we’ve lost; for instance, they still lay eggs. So we can use them to trace the changes that have occurred as we went from being a reptile, to having fur to making milk to having live-born young. (LiveScience)
A platypus who was a biologist could just as easily say something along the lines of
The lineage of which humans are a part is a very ancient offshoot of our mammalian family tree, so it was 166 million years ago that we last shared a common ancestor with humans, and that puts them somewhere between mammals and reptiles, because they lack a lot of specialized characters that we have gained but the ancestral amniote also lacked; for instance, they have no electroreception, no bills, no webbed feet, and no venom. So we can use them to trace the changes that have occurred as we went from being a reptile, to having fur to making milk to having our specialized features.
Indeed, this is how the evolution of platypus venom was studied. Humans possess the ancestral, non-venom-related version of the genes that were duplicated and then co-opted in platypus in their novel role.
Fortunately, several people have posted articles attempting to clarify this:
- What The Platypus Genome Is and Isn't (Adaptive Complexity)
- Who are you calling ‘primitive’? (Nimravid)
- Platypus sex chromosomes and basal-equals-primitive (Genomicron)
- The platypus genome (Pharyngula)
More generally, you can read about evolutionary trees, and hopefully be able to spot fallacies in media stories:
- Understanding evolutionary trees (Evolution: Education and Outreach)
- The tree thinking challenge (Science)
- College students' misconceptions about evolutionary trees (American Biology Teacher)
- Do early branching lineages signify ancestral traits? (Trends in Ecology and Evolution)
- Understanding phylogenies (Understanding Evolution)
- Phylogenetc systematics (Understanding Evolution)
- Do you understand evolutionary trees? (Part One) (Genomicron)
- Do you understand evolutionary trees? (Part Two) (Genomicron)
- Phylogenetic Fallacies: Branching From a Main Line (Genomicron)
- Phylogenetic Fallacies: Early Branching Must Mean Primitive (Genomicron)
- Understanding evolutionary trees (Nimravid)
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