Recent critter encounters

Posted on April 13, 2013 by Troy Britain

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!]

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.

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.

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.

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…

Creationist foists “fraudulent” embryo picture on his readers

Posted on July 26, 2012 by Troy Britain

I decided I am not going to bury the lead on this one. Brian Thomas of the Institute for Creation Research (ICR) just posted another in a long line of creationist screeds attacking the evidence for evolution from comparative embryology, which as usual claims that the evidence is based on fraud and pins much of the blame for it on 19th century biologist Ernst Haeckel.

I began writing a rebuttal straight away but then I happened to take a second look at the bright pink image of an embryo atop the article and it brought me to a sudden halt. So, having backed up, let me start again.

Thomas: German zoologist Ernst Haeckel is perhaps most famous for defending evolution with the argument that creatures replay their evolutionary past when developing in the womb. …In his zeal to promote evolution, Haeckel foisted faulty embryo sketches onto his readers, and the zeal of his followers has perpetuated those falsehoods for over a century. (Thomas 2012, emphasis mine)

Yeah, about that…

That’s right, yet another irony meter has been reduced to subatomic particles by a creationist.

Read on»

There’s something fishy about that fish

Posted on May 16, 2011 by Troy Britain

Institute for Creation Research President Dr. John Morris has taken to recycling; in this case he’s dusted off some nonsense from an article he wrote 3 years ago titled “Evolution’s Biggest Hurdles” (Morris 2008) and repackaged it as “The Biggest Problems for Evolution” (Morris 2011).

As I usually do I started out writing a point by point re-rebuttal to Morris’s new article; even though I already wrote a fairly extensive rebuttal to the earlier version. However, as I was writing, and as it got longer and longer, I realized that I was going to bury the lead way too deep. So, I am dropping most of the rehashing and jump to the new issues I want to address.

First though just a little of the lead in for context:

Morris: Even though the gaps in the fossil record are found between each basic animal type, there are two huge gaps in particular that should be emphasized. The evolutionary distance between single-cell organisms and the vast array of multicellular, highly complex marine invertebrates precludes even rapid evolution.

Oh boy, this is déjà vu all over again.

From earlier context (see below) the “rapid evolution” he is referring to here is supposed to be punctuated equilibrium, however P.E. about apparent, geologically, “rapid” transitions (say a few tens of thousands of years) and concerns species level transitions (like those necessary to evolve horses and zebras from a common ancestor) not multicellular organisms from unicellular ones. Again, I’ll have more on his use of P.E. below.

As for the gap between unicellular and multicellular organisms the (really) short answer is: choanoflagellates (colony forming single celled organisms that are strikingly similar to cells found in sponges called choanocytes). Again, see my earlier post “You can tune a piano but you can’t tunicate” for more.

Morris: In the supposedly 600-million-year-old layers of rock designated as Cambrian (which contain the first appearance of varied multi-cell life), sponges, clams, trilobites, starfish, etc., are found without the required evolutionary ancestors.

Wrong, wrong, wrong. I covered this before as well.

1) There are fossils of multicellular organism in Precambrian strata (the Ediacaran biota for example).

2) Amongst those Precambrian multicellular organisms are sponges and jellyfish.

3) “Clams” (bivalve mollusks) are known from the Cambrian but only from few tiny extinct types.

4) Starfish or sea stars (Class Asteroidea) fossils do not appear in the fossil record until the Ordovician.

Morris: The gap from marine invertebrates to the vertebrate fish is likewise immense.

Again, Dr. Morris doesn’t want you to know about invertebrate chordates or the evidence for a relationship between chordates and echinoderms. I’ll have more on this in a few moments.

OK, now we get to it:

Morris: To make matters worse for the evolutionists, fish fossils are also found in Cambrian strata.

If we define the colloquial term “fish” in the usual way (in reference to all aquatic, gill bearing, vertebrates) then yes, a few genera of “fish fossils” have indeed been found in Cambrian strata.

However the word “fish”, is not a scientific term, so the question must be; exactly what sort of “fish” has been found in the Cambrian strata? Dr. Morris does not grace his readers with any further comment on this question; there is however a prominent illustration of a fossil fish that accompanies the article. Here is a screen shot of the page the article appears on:

And here is a larger version of the fish fossil picture:

I think it is fair to say that most people who are not particularly familiar with vertebrate phylogeny and paleontology—including most of Dr. Morris’s readers—might assume when they read in his article that “fish fossils are also found in Cambrian strata” that the large centrally displayed picture of a fossil fish might in fact be one of the Cambrian fish Morris is referring to.

Read on »

More from Inside Nature’s Giants

Posted on October 16, 2010 by Troy Britain

Two more episodes from the excellent television series Inside Natures Giants are now available for viewing on YouTube. As I wrote in a previous post, this is a fascinating zoology program wherein the bodies of various large animals are dissected to demonstrate the details of their anatomy. This is combined with discussions of the living animals and their natural history with occasional incites from Richard Dawkins about evolutionary biology.

First of the newly available episodes is a two for one in which both a lion and tiger are examined, contrasted and compared. Here is part one of four:

A play list for the rest of the parts can be found here.

In my previous posting on this series I wished for them to focus an episode on something like a giant squid so as to show something on invertebrate anatomy and my wish has come true. Here is part one of five:

I couldn’t find a play list for this episode so here are individual links to the different segments: part 2, part 3, part 4, and part 5.

As before I really cannot speak more highly of this program. It is fascinating television for anyone with even the slightest curiosity about the natural world and a absolute must see for anyone interested in biology, zoology and evolution.

Gush, gush, gush!

[Thanks to P.Z. (squee) Myers over at Pharyngula for the heads up on the squid episode and to the WhyEvolutionisTrue YouTube channel for hosting the videos!]

Inside Natures Giants

Posted on July 18, 2010 by Troy Britain

I recently stumbled upon (on YouTube) a BAFTA award winning British TV series titled Inside Natures Giants and I’ve fallen in love. What we have here is a television show in which various large animals, all vertebrates so far, are dissected on camera (and often in front of a live audience of students) by a team of biologists in order to show the details of their anatomy while presenting elements of their physiology, natural history and evolution (including commentary by evolutionary biologist Richard Dawkins).

So far the show has dissected an Asian elephant, a fin whale, a Nile crocodile, a Rothschild giraffe, a great white shark, a Burmese python, and most recently (unfortunately not yet available on YouTube) a two for one, lion and tiger combination.

I’m hoping they work in a ostrich or emu in there sometime soon and maybe a giant squid or octopus to show some invertebrate anatomy as well.

These programs deal with the dissection of actual animals in graphic detail so if you’re squeamish at all you might find them difficult to watch, however this show is an absolute must see for anyone interested in zoology and evolution.

Of particular interest was the dissection of the giraffe. Among the various interesting adaptations towards tree top browsing is a classic example of one of the cloven hoofprints of evolutionary history, the recurrent laryngeal nerve; the dissection of which has apparently not been done (according to one of the scientists in the show) in a giraffe since the 1830’s.

Here is the first episode of the first series on the Asian elephant: