Consilience and whale evolution

Way, waaay back in December of 2005 (ye gods has been ten years already?!) I wrote a Feedback response on the Talk Origins Archive to a question about the vestigial pelvic bones found in modern whales. In this case the questioner did not believe them to be truly vestigial, no doubt due to holding erroneous beliefs regarding the subject. In my response I of course took the time to correct their faulty views, however I also used the opportunity to talk about the concept of consilience wherein multiple independent lines of evidence converge on a single explanation, giving us greatly increased confidence that those explanations (hypothesis/theories) are likely to be accurate reflections of reality, i.e. “true”. 

I have now and again thought of going back and using that post as a spring-board for a more detailed examination of this subject and who knows, I may still do so someday. In the meantime however, here is a great video from Stated Clearly that I ran across on Facebook recently that uses the same topic—whales—to essentially do the same thing I did all those years ago; make a point about the consilience of evidence pointing to a pretty definite conclusion with regards to not just the ancestry of cetaceans but the evolution of life in general. Better they include more details than I did and it has animations.

Check it out:

I miss answering the feedback question on Talk Origins…

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Creationism Nit: Archaeocete legs

This will be a departure from my typical novel length dissection of a creationist article and will instead be a short look at a single creationist gaffe. Perhaps I will make this into a series, we’ll see. Anyway, today’s nit will be picked with young Earth creationist Dr Carl Werner (a medical doctor).

I recently acquired a copy, of what I believe is the 1st edition, of his book Evolution: The grand experiment (2007, 2nd printing 2009, coauthored with his wife Debbie Werner) and while skimming through it I noticed a little error on page 57, which is chapter 5 of the book and is apparently meant as a refutation of the evidence for evolution from comparative anatomy. In this particular case he is discussing the homology of various tetrapod forelimbs (yellow highlighting mine):Werner_whale

The “nit” in this case is his illustration of the forelimbs of a whale in the dark blue circle above. When I saw it I immediately  recognized that it was not in fact the forelimbs of a whale but rather the hind limbs of one. In this case those of an extinct archaeocete, most likely those of Dorudon (image source).

The skeleton of Dorudon.

And these are the hind legs of Dorudon (image source):

Dorudon hind legs at the Smithsonian Museum

For comparison here are a couple modern whale forelimbs:

Blue whale (Balaenoptera musculus).

Pacific white-sided dolphin (Lagenorhynchus obliquidens).

Clearly what Dr. Werner has pictured are not the forelimbs of a modern whale, rather my money is on them being the hind limbs of Dorudon. Is it a huge deal? No. It is just another example of sloppy creationist research (I mean if a printing press operator recognizes archaeocete legs when he sees them, come on).

Nit. Picked.

Relevant Links

Missing footage from the Nye v. Ham debate!

Wow, OK… One like, no comments, I guess it was just me (and one other person).

A “Darwin fish” of a different sort

A little in-joke…

The evolution of feathers in about 3 and a half minutes

By Carl Zimmer:

[Hat tip to Brian Switek.]

Recent critter encounters

As I continue to try and adapt to having a significantly longer commute to work, settle into our rental house, and generally try to get my crap together, here are some pictures of some critters I’ve encountered over the last few months.

First a mollusk:

I discovered this rather large (approx. 10cm) slug making its way across my front walk. Not sure about my ID but I’d say it was possibly a Limacus flavus, which would make this an introduced ALIEN SLUG! [Scream!]

Limacus

Secondly a couple different arthropods, one terrestrial and the other aquatic:

This dangerous little bugger was hitchhiking in a load of horse manure that my mother was unloading from the back of her pickup truck. A centipede, probably a Scolopendra polymorpha. After I told my mother that I wasn’t interested in adopting it she ended up feeding it to her chickens, which was probably a little spicier than their usual fare.

centi-sm

OK, there is a bit of a set up to our next crawly, or rather swimy critter. I was on my way to work one morning and while driving by a vacant lot around the corner from my house, I noticed three adults standing around a large puddle in middle of the lot that was left over from some recent rain. My brain noted that this was an unusual thing to see, so I slowed down a bit and saw that a couple of them were holding small fishnets, of the sort that an aquarist might keep handy. Quickly running through the possibilities of what three adults with fishnets standing around a small ephemeral body of water in a generally arid environment might be up to and my brain instantly hit upon what seemed to be the only logical conclusion…BIOLOGISTS!

Unfortunately I was already a little late for work and couldn’t stop and talk to them, however I immediately vowed to myself that I would visit the puddle ASAP to see what might have drawn a trio of probable biologists to this vacant lot. So on my way home from work I stopped at the lot and checked out the puddle.

At first I didn’t see anything but once my eyes adjusted to what I was looking at I noted some small (maybe 2cm) things swimming fairly vigorously around the puddle. At first I thought that they might be fish, perhaps Gambusia which are often stocked in our local waterways to control mosquitoes. This wasn’t totally crazy as there is a catchment basin immediately adjacent to the lot and I thought that, while it was unlikely, it might be possible for some Gambusia to have somehow made it into this puddle.  However given that this was a very ephemeral body of water and that Gambusia would be considered “junk fish” by an ichthyologist I quickly dismissed this idea.

Looking a bit closer at the tiny swimming creatures I realized what their true nature was and why thy might be of interest to biologists became much less of a mystery. They were fairy shrimp, possibly of the Family Streptocephalidae, some members of which are very endangered. In this case possibly Streptocephalus woottoni A.K.A. the “Riverside fairy shrimp“, though this puddle was a little shallow (under 30mm) for the normal bodies of water that S. woottoni are supposed to inhabit.

Anyway, after seeing that they were indeed fairy shrimp I rushed home and got one of my critter keepers (a small plastic aquarium) and fashioned a small, pitiful, net out of a coat-hanger and one of my wife’s old nylon stockings. Pitiful as my jury-rigged net was, it allowed me to catch a few of the shrimp.

Fear not for the shrimp though, after I photographed them (which isn’t an easy thing!) I returned them to their puddle which remained habitable for three or four days longer.

Shrimp1

Shrimp3

Last but not least a couple different chordates, in this case both mammals:

While driving through a local rural area (Reche Canyon) my wife and I spotted a herd of feral burros (Equus africanus asinus) that we had heard (get it?) lived in the area. I wasn’t able to get too close to them and only had my cell phone camera so these are not the best pictures. However if you look carefully at the second picture below you’ll get a glimpse of some “hot donkey action” going down (brown chicken, brown cow!).

Apparently there is something of a mystery involving these burros lately. It seems that several of the newborns have gone missing and it becoming a concern for the locals who watch over them.

ass_2

ass_1

Finally a rough pair of middle aged male apes (H. sapiens). Yours truly with Dr. Sean B. Carroll Professor of Molecular Biology, Genetics, and Medical Genetics at the University of Wisconsin–Madison at U.C. Riverside on 2-11-2013. Dr. Carroll had just given a very entertaining talk: Remarkable Creatures: Epic Adventures in the Search for the Origins of Species about the adventures and scientific contributions of Alfred Russel Wallace, Charles Darwin and Henry Walter Bates in honor of Darwin Day 2013 (Photo and my shirt by Lani Britain, a.k.a. Mom).

OK, so this wasn’t a scathing dissection of creationist silliness, but it was something…

Zebras: Nature’s Ultimate Prey

In a related story:

God Admits Humans Not Most Impressive Creation

Loves me some The Onion