Recently in genetics Category

As Grant said earlier, there is a rich mine of potential posts in this particular website... This time, let's review its author's take on the phylogenetic relationship between Homo sapiens and Pan troglodytes.

We are indeed linked to chimpanzees – by a common Designer.

In my last post on a 'creationist biology curriculum' I asked the question: what, exactly, do they teach? Over on the Sciblogs site (where this blog is syndicated), a commenter answered by pointing me at another school's curriculum. As I read through it, I could feel the area beneath my collar getting distinctly heated.

This was partly due to the sections listing Commonly accepted science we believe in and Commonly accepted "science" we do not believe in. What we have here is an a priori assumption about the world, followed by rejection of anything that doesn't match that particular worldview. This is not how good science is done. (And note the use of scare-quotes denoting the science that the authors don't believe in.) And this makes me wonder just how well their students will understand the overarching strand of the national science curriculum, the nature of science.

This comes at an opportune time for those of you teaching the Human Evolution content - and for those looking around for some follow-up reading :-) The Howard Hughes Medical Institute has a whole lot of free biology education resources available on line, and this upcoming webcast looks to be wonderful stuff: Bones, Stones, & Genes: the origin of modern humans. It's completely free; you just need to register for it. You can bet I'll be doing my best to be there!

And hat-tip to PZ, who as usual finds out about these things first :-)

One of my students sent me the link to this video (obviously thinking I could do with a bit of light relief from marking!): Futurama's take on evolutionary arms races :-)

Apparently this is a question that has been known to keep some biologists awake at night. (Can't say I'm one of them; my insomnia is caused by other, equally pressing issues LOL)

Anyway, ERV has written a lovely post looking at this: apparently it's all to do with metabolic pathways and endogenous retroviruses. Go over there & soak up the goodness :-)

(And sleep well.)

We understand a fair bit, these days, about the evolution of the complex, 'camera-type' vertebrate eye. Not that this has stopped creationsists (most recently the 'intelligent design' camp as represented by the Discovery Institute) from arguing that the eye is an excellent example of How Evolution Is Wrong - what, they ask, is the use of half an eye? (The answer is, plenty, if an organism can detect the direction of a light source, or the movement of a predator - & in fact it's been suggested that the evolution of even the most basic photoreceptors may have had a hand in the rapid increase of animal taxa during the Cambrian.)

However, one of the unanswered questions (& thus fertile ground for creationists) has always been, when? Just how deep in time is the origin of the vertebrate eye & its specialised light receptors. A new paper just out may help us to answer that question (Passamaneck et al. 2011).

Once upon a time, a long time ago when I was a high school student, I remember being taught about human evolution as a fairly linear, straightforward narrative. OK, there were those 'robust' australopiths (aka Paranthropus) on a dead-end side branch, but otherwise species followed species - beginning around 14 million years ago with Ramapithecus (or Sivapithecus) - until you got to us. I don't remember being taught much about 'new' finds, either, although there must have been some; it all came across as pretty much done & dusted. In other words, we didn't learn much about the nature of science, either; there was no sense that new discoveries could overturn existing understandings.

I had a quick web-surf in between walking the dog (before it got too hot) & doing some paperwork. And behold! there was a post by PZ entitled My mouse has two daddies. So the paperwork had to wait a bit :)

PZ's writing about a rather clever - & intricate!) - piece of work that's resulted in a baby mouse whose genome has absolutely no contribution whatsoever from a female mouse - it's all from 2 males. A fascinating piece & well worth a read.

Now, back to what I was supposed to be doing...

I spent yesterday up in Auckland, running a schol bio preparation day. (And thanks to Mike, Cindy, BEANZ & the Auckland Science Teachers Association) for setting it up.) I do enjoy these sessions (& hopefully the students do too!) as I like the interactions with students & they always ask nice, challenging questions.

Anyway, after we'd finished the main proceedings of the day, someone came up & asked if I'd heard of the 'killer Neandertal' hypothesis, & what did I think of it? Was it a good explanation for the evolution of modern humans? The quick answer was, no I hadn't, so couldn't really comment - but I'd go & have a look :)

Prominent creationist Ray Comfort once (in)famously commented that the 'design elements' that make up a banana, including its so-convenient shape, are evidence for the existence of a Designer. A comment that has been pretty resoundingly debunked - unsurprisingly, since the banana-as-we-know-it is due in large part to the hand of man, selecting for those features of bananas that make them desirable as a food - lack of seeds (wild-type, uncultivated bananas have almost more seeds than flesh) & that wonderfully unzippable peel. Something that last year's Schol Bio examination asked students to think about.