Recently in evolution Category

That's the title of Susan Musante's paper in the latest issue of Bioscience (& many thanks to David Winter for sending it on). It's a summary of some key points made by speakers at an NAS convocation called "Thinking evolutionarily: evolution education across the life sciences."

Now, I find science fascinating, exciting, & endlessly interesting, & I'm sure my colleagues feel the same. The thing is, how to pass all that on to our students? As I've said before, simply providing them with quantities of facts is not going to do it. At the convocation, several speakers stressed that

[simply] regurgitating the biological knowledge generated by the scientific community or conducting "cookbook" laboratory experiments does not result in genuine understanding or excitement on the part of students... Instead, the nature and process of science, the unifying concepts and connections to the real world, and the problems encountered and discoveries made by scientists are what make biology come alive.

One of my tasks at the moment it the revision/rewriting of the study guide (along with my actual lecture notes etc) for my A semester first-year biology class. As part of that I'm reviewing some of the material I give the students to read & came across a previous post of mine on the relationship between atmospheric oxygen and the size of eukaryote organisms. And I liked it (still), so thought I'd repost it here :-)

The earliest fossils we have are of prokaryotes - a major taxonomic grouping that includes both bacteria and members of the Archaea (things like blue-green algae, aka cyanobacteria). And like modern prokaryotes, those early life-forms were tiny. Most of us are far more familiar with some of the eukaryotes, and perhaps a major reason for this is that we can see them: they are orders of magnitude bigger than microbes. And an interesting question is: what sort of trajectory took some forms of life from the tiny to the ginormous? Was there a smooth upward trend in the maximum size of living things? Or did things progress like a learner driver - by bunny-hops?

Just a heads-up for teachers & students: next month Chris Stringer will be giving public lectures on human evolution in Auckland, Wellington, Christchurch & Dunedin. (No Hamilton talk! I am sad :-( I've got an all-day meeting that means I'd never get up to the Auckland  event in time.) From the latest Royal Society "Alert":

Professor Chris Stringer: ‘Origin of our species, Neanderthals and the Early Human Occupation of Britain and Europe’, February 2012

Professor Chris Stringer answers some of the big questions:  How can we define modern humans, and how can we recognise our beginnings in the fossil and archaeological record? How can we accurately date fossils, including ones beyond the range of radiocarbon dating? Has human evolution stopped, or are we still evolving? What can we expect from future research on our origins? 

Professor Chris Stringer is in New Zealand by invitation of the Allan Wilson Centre for Molecular Ecology and Evolution and his public talks are supported by the Royal Society of New Zealand.  Details for booking tickets are available at http://www.royalsociety.org.nz/events/origin-of-our-species/

• Auckland, 6.00 pm, 22 February, Auckland War Memorial Museum;
• Christchurch, 6.00 pm, 23 February, C1 Central Lecture Theatre, University of Canterbury;
• Dunedin, 6.00 pm, 24 February, St David Lecture Theatre, University of Otago;
• Wellington, 6.00 pm, 25 February, Embassy Theatre, Courtenay Place.

From today's "Letters to the Editor" in today's NZ Herald:

Your correspondent correctly states that Charles Darwin's theory of evolution is under threat.

The main threat, however, is not coming from "conservative religious school." It is coming from science.

Well, as a scientist, this is news to me. What scientific evidence does our correspondent present in support of this supposed 'threat'?

 And yes, punctuation & grammar skillz, I has them :-) That apostrophe really is in the right place - read on to find out why.

The tale of the panda's thumb is well-known, & an excellent example of how the action of natural selection can result in jury-rigged solutions to problems: a result that works, but not necessarily a perfect result. I first encountered it way back when, through reading Stephen Jay Gould's wonderful book of the same name**.

A book which refers to the familiar black-&-white giant panda (Ailuropoda melanoleuca). I'd never really thought about it before, but of course we have 2 species of panda: the big fellas, & the much smaller red panda (Ailurus fulgens). Do they have 'thumbs' too?

As a post by Brian Switek shows, the answer is 'yes; yes, they do'. And this is really interesting, as the two pandas aren't closely related. Giant pandas are bears, while reds are more closely related to raccoons. Yet they both have modified a modified wrist bone, the radial sesamoid, that functions as a thumb and allows them to grip & manipulate bamboo - a lovely example of convergent evolution.

**The original essay, with the title The panda's peculiar thumb', is reproduced here.

 Over on 'of trees and birds and other things' Jarrod points out why it's not a terribly good idea to base your view of a scientific issue on a single story in the popular press... (& hat-tip to David Winter on the atavism, who alerted me to this new evolutionary blog!) For the teachers & students who read my blog: Jarrod has an interest in forest ecology & his research area is evolutionary ecology, so I think it will be well worth dropping over to his place from time to time :-)

PS apologies for the original 'dud' link - all fixed now :-)

 As a distraction (or should that be 'procrastination'?) from what's currently filling up my diary (ie processing student enrolments), I've decided to look at another of those 'science' statements from the school documents I linked to in my last post. "What about the archeopteryx?" they ask. Well, what about it? This, from their webpage:

The archeopteryx is an extinct, unusual bird. Two fairly complete skeletons have been found in Europe.

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.

 I was spurred to write this by a comment  Grant made on my previous post on the various NZ political parties' stances on science education. In that post I linked to the website of a 'special character' school: one with a religious underpinning & which states that they replace 'evolution' with 'creation' in the school's science curriculum:

All strands are covered as stated in the National Curriculum: The Living World, the Physical World, the Material World and Planet Earth and Beyond. As a Christian school we change the sub-strand called 'Evolution' to 'Creation'. This links with our extra subject Creation Studies.

Which leads me to wonder exactly what such schools do teach in science classes... 

It wasn't all koala-spotting on our trip across the ditch (the Tasman Sea, for those readers not familiar with New Zild as it is spoken, lol). Apart from the glories of Melbourne (lovely old buildings, the stunning King Tut exhibition in Melbourne Museum, floral Doc Marten boots mmmmmm - & of course the restaurants of Lygon Street!), we also spent time on the Great Ocean Road & with friends in Ballarat.

Now, our friends know how much the husband likes fossils, & so for our visit they'd scoped out a few sites that weren't too far afield, & last Sunday we drove out to Castlemain, picked up a friend of the friends, & headed out to see what could be found. We were sort of expecting a canyon or something, so were slightly surprised to end up out in the bush, not far from a road. It turned out that the road had been driven through some ancient rocks, around 450 million years old, & there were rich pickings in the roadside spoil heaps.