Third eagle egg!

February 11, 2011 • 12:22 pm

Several alert readers have reported that the female eagle at the live EagleCam has laid a third egg.  It’s been hard to verify since the eagles are sitting on the nest continuously, and it’s been snowing, too.  But here’s the proof:

The site relates that the eggs were laid almost exactly three days apart:

  • First egg laid February 3, 2011 at 2:49 p.m.
  • Second egg laid February 6, 2011 at 4:25 p.m.
  • Third egg laid February 9, 2011 at 5:55 p.m. (first sighting of egg 8:46 a.m., February 11, 2011)

Now one reader has predicted darkly that at least one eaglet won’t survive; and indeed, that’s the usual result when three eggs are laid. But these birds are diligent, and in each of the last two years they’ve laid three eggs and fledged all three chicks.  The pair has been nesting in the Norfolk Botanical Garden since 2004, and have fledged a total of 15 chicks. Now that’s fitness!

Besides the opportunity to get a rare and intimate view of reproduction in this amazing bird, one of the attractions of EagleCam for me is the incongruity of a noble, serious, and almost angry-looking raptor tending its young with infinite solicitude.  It was sad but touching to watch the mother sitting on the eggs while it was snowing, occasionally shaking the snow from her feathers but never budging from the eggs.

If you’re following these birds, be glad that (knock on wood) we’ll have interesting things to see until the young fledge in August.

How long do bald eagles live? One informative site says that the lifespan is roughly 15 to 20 years in the wild, although one bird lived at least 48 years in captivity.

Dawkins: a Protestant atheist

February 11, 2011 • 6:24 am

I’m not sure what The Guardian intended by setting up the Comment is Free section, but I’m pretty sure they didn’t mean to publish essays so dire that they wouldn’t pass muster in an undergraduate composition class. Today’s specimen is a critique of Richard Dawkins by one Thomas Jackson.  I thought I’d heard every possible criticism of Dawkins, but Jackson has a new one:  Dawkins, in his science, is unconsciously engaged in Protestant mythology!

My problem with Richard Dawkins is not that he is an atheist. I admire that. It’s that he’s a Protestant atheist. Religion, many think, has been slain by the experimental method of science. Beginning with Galileo’s experiments on free fall, science has succeeded because it is value-free, objective and proves its points not by nebulous belief but by rigorous logic and verified proof. This is a complete misunderstanding.

The history of the experimental method shows us that, far from being value-free, it was deeply enmeshed with a Protestant myth, as in its post-Protestant phase it continues to be.

What is that “Protestant myth”?  The idea that God is not a part of nature itself (a view that Jackson sees embodied in Catholicism), but a deity outside it, one who set up the universe so it could be understood through rational investigation.  But Jackson’s article is so poorly written and organized that it’s hard to see what his beef is.  Why is “Protestant deism” more wrong that the idea that god inheres in nature like cuteness in a kitten?  And why is the idea that the world is comprehensible through empirical study a “myth”?

Who knows?  All one gets from Jackson’s babble is that he doesn’t really like Richard Dawkins.  And so we get  stuff like this (how many deepities can you spot?):

Dawkins’s understanding of Catholic theology seems to be nil. He thinks that religion teaches that God constructed the world like a watch, science has shown it is able to construct itself, therefore there is no God. How Protestant is that? The intelligibility of God is so bright, according to the great Catholic mystics, it overwhelms our minds with darkness, and can only be penetrated by the will. Science is beginning to suggest that reality might perhaps be like that. Quantum physics is bewilderingly irrationally rational.

Dark matter? Non-locality? An infinity of universes? In my experience contemplative prayer delivers. It is as inescapably compelling to the emotions as mathematics is to the intellect. Poor old Richard thinks that prayer means asking God to suspend the laws of the universe to stop it raining on the day of the church fete.

Poor old Richard, who simply doesn’t see that every religious person in the world is just like Jackson, who himself knows that there’s no point, save a contemplative peace, to importuning god.  We should give a name to the fallacy that every religious person in the world has sentiments precisely identical to those of a liberal believer.

 

The hind legs of whales

February 10, 2011 • 11:00 am

by Greg Mayer

Snakes are not the only tetrapods (or even lizards) to have lost their legs. Whales have lost their hind legs (the front ones are now their flippers), and we have a pretty good fossil record of how they did so, thanks in large part to the work of Phil Gingerich of the University of Michigan Museum of Paleontology (see his great whale evolution site here) and his collaborators.

Although whales lack external hind legs (except as rare teratologies), they do have internal rudiments of the hind limbs and pelvic girdle, as I was reminded during a recent visit to my and Jerry’s alma mater, the Museum of Comparative Zoology, where one of the Museum’s killer whale skeletons now hangs in the building across a new courtyard: note the remnant hind limb girdle at lower left.

Killer whale, Orcinus orca; note remnant hind limb girdle at lower left (the MCZ is the building in the background).

Here’s a closer view.

Killer whale hind limb girdle remnant.

In addition to the killer whale skeleton, there’s also a bottlenose whale skeleton; here’s its remnant hind limb girdle.

Bottlenose whale, Hyperoodon ampullatus, hind limb girdle.

Both whales were hung in this new building (which is where the MCZ parking lot was in my and Jerry’s days) at the initiative of the MCZ’s director, Jim Hanken. The figure below, from Phil Gingerich, shows some of the fossil whales through which limb loss has been traced.

Whale evolution.

Here’s his caption for the figure (go to his website for full citations to the papers mentioned):

Figure 1. Skeletons of the archaeocetes Dorudon atrox and Rodhocetus balochistanensis compared to that of Elomeryx armatus, which is here taken as a model for the extinct group of artiodactyls (Anthracotheriidae, s.l.) that we now think may have given rise to archaic whales. Pakicetus has a distinctive skull and lower jaw, but is not demonstrably different from early protocetids postcranially. Note changes in body proportions and elongation of feet for foot-powered swimming in Rodhocetus, then later reduction of the hind limbs and feet as the tail-powered swimming of modern cetaceans evolved in Dorudon.

A. Elomeryx drawing from W. B. Scott, first published in 1894. B. Pakicetus skull from Gingerich et al. (1983). Terrestrial interpretation is pure speculation: what little is known of the skeleton resembles Rodhocetus. C. Rodhocetus skeletal reconstruction from Gingerich et al. (2001). D. Dorudon skeletal reconstruction from Gingerich and Uhen (1996). Figure may be reproduced for non-profit educational use.

I showed photos of the hind limb remnants of Maiacetus, Basilosaurus, and Dorudon skeletons at the USNM in an earlier post.

(Thanks to Jon Losos for checking whale ID’s for me.)

Brief perigrination, with beautiful sentences

February 10, 2011 • 7:07 am

I’m off to Wisconsin today for Darwin Day.  If you’re anywhere near Whitewater this evening, do drop by for the talk.

There will be a brief hiatus in my posting,

but I’ve asked Greg and Matthew to fill the gap.

In the meantime, I’ve noticed that Stanley Fish has just published a new book, How to Write a Sentence.   I was surprised to see this, since his turgid productions in the New York Times didn’t give me a lot of confidence in his writing skills.  But maybe he wrote better when he was younger.  At any rate, I suggest that for our mutual edification and amusement we each contribute one of our favorite sentences from literature.

Here’s my contribution, which I’ve highlighted before. It’s the last sentence in The Dead, by James Joyce:

His soul swooned slowly as he heard the snow falling faintly through the universe and faintly falling, like the descent of their last end, upon all the living and the dead.

Or you can suggest something from science, too (or both), like this familiar sentence:

It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material.

Biology updates: snake legs, cat rolling, frog teeth and more

February 10, 2011 • 6:41 am

There hasn’t been a lot of terribly exciting evolution news lately, but there are a few items of interest (references to papers are at the bottom).

Snake legs:  It’s clear from various lines of evidence, including molecular data and paleontology, that snakes evolved from lizards who lost their legs.  But fossils of the transition are very, very rare, for snakes have fragile bones and vestigial limbs are hard to see in fossils.   A new paper in the Journal of Vertebrate Paleontology by Alexandra Houssaye et al., however, analyzes an amazing specimen: a half-meter long aquatic snake, 95 million years old, from Lebanon.  It’s a marine snake, and there’s controversy about whether these marine reptiles were the ancestors of all modern snakes or simply an offshoot of a terrestrial ancestor.  Likewise, we don’t know if snakes evolved from terrestrial lizards or, perhaps, aquatic ones (there’s at least one aquatic lizard: the Galápagos marine iguana).  Reagardless of these debates, the Houssaye et al. paper is nice for its remarkable analysis, via a noninvasive method (“synchrotron-radiation computed laminography”, or SRCL, whatever that is) of the vestigial legs of this early snake.

Here’s the specimen; it’s broken, so the tail segment, containing the tiny legs, is at the top right, next to the snake’s head.

And here’s the image from the SRCL scan.  Images B and D show the tiny leg, enlarged from the boxed segment in image A.  “F” is the femur, “T” the tibia, and “Fi” the fibula, all clearly homologous to the leg bones of lizards and other vertebrates.  Note that the scale bar is 1 mm long, so the leg is about 7 mm long (roughly a third of an inch).

The evolutionary origin of snakes is still a bit unclear, but what is clear is that they evolved from reptiles with legs.  The depiction of the vestigial legs here (surely on the way out, since they impeded swimming by causing drag) is a nice piece of evidence for evolution.

A description of the discovery from LiveScience is here (link seems to be broken, maybe temporarily).

Why do cats roll? Mark Abraham of the Guardian highlights an old paper (1994) by Hillary Feldman, who wanted to answer the age-old question, “Why do cats roll?”  (Citation below, the paper seems to be free.) Observing cats in a large enclosure, Feldman found that they roll for two reasons.  Females roll in oestrus as a form of sexual invitation to males, and males roll before other males as a form of submissive behavior.  These may not be surprising to cat owners, although the “roll” before a human may represent not submission, but a request for a tummy rub (viz. Baihu).  At any rate, before this study it wasn’t known whether cats showed the same kind of submissive rolling seen in social canids.

Sperm competition. Tim Birkhead, a professor at Sheffield in England, has done pathbreaking work on sperm competition in birds.  Over at The Browser, he’s interviewed about this cool phenomenon, and he recommends five relevant books, one by William Eberhard which I like a great deal.  And the Krebs and Davies book, Behavioural Ecology, is a classic that helped shaped that field.

Cuttlefish behavior. Over at her website, Karin Bondar highlights new work on cuttlefish, showing that exposing embryos to the odors of different prey can affect the feeding preferences of those animals after they’ve hatched.  There’s also a nice video showing an animal changing color.

Frog teeth violate Dollo’s Law. Dollo’s “Law” (really a generalization) is an evolutionary principle stating that once a trait is lost in evolution, it won’t reappear in exactly the same form.  The idea is that if a feature is lost by inactivating or changing the function of genes that produced it, it’s unlikely that those exact gene sequences will re-appear (or that new genes will mutate) to produce a trait that has precisely the form of the lost one. (Another interpretation is simply that it’s unlikely for a lost trait to reappear in a similar form.)  There have been some exceptions to this “law”, and now we have a new one: a paper in Evolution (yay, us!) by John Wiens of Stony Brook,  showing that a species of frog from the Neotropics (Gastrotheca guentheri) has re-evolved mandibular teeth (teeth in the lower jaw).  These teeth, lost in frogs over 200 million years ago, were regained in the ancestor of this species several million years ago.

G. guentheri (photo from Arkive).

Gastrotheca are called “marsupial” frogs because some females have a brood pouch on their backs where they deposit and carry fertilized eggs. In other species males guard the eggs in the ground, and then take the tadpoles into their pouch, carrying them around until they develop into froglets.

The Wiens paper is here, and there’s a blurb in The New York Times. I’ll try to get a picture of the teeth from Wiens.

h/t: Alexandra Houssaye and Matthew Cobb.

___________

Feldman, H. 1994.  Domestic cats and passive submission. Anim. Behav. 47: 457-459.

Guibé M, Boal JG, & Dickel L (2010). Early exposure to odors changes later visual prey preferences in cuttlefish. Developmental Psychobiology, 52:833-7.

Houssaye, A., F. Xu, L. Helfen, V. de Buffrénil, T. Baumbach and P. Tafforeau. 2011.  Three-dimensional pelvis and limb anatomy of the Cenomanian hind-limbed snake Eupodophis descouensi (Squamata: Ophidia) revealed by synchrotron-radiation computed laminography.  J. Vert. Paleontology 31:2-7.

Wiens, J.  2011.  Re-evolution of lost mandibular teeth in frogs after more than 200 million years, and reevaluating Dollo’s Law. Evolution in press: doi:10.1111/j.1558-5646.2011.01221.x

Video: eagles’ second egg

February 9, 2011 • 2:00 pm

As promised, I’m posting Sunday’s video of the bald eagle from EagleCam (in Norfolk, Virginia) laying her second egg.  The production of this egg was much more difficult than the first, and I’ve received expressions of sympathy from women who have borne children.

Note the female’s inspection of the egg immediately after it was laid.  “Did I do that?”  If all goes well, we should have bobbleheads in about a month.

And, from an alert reader, here’s a visual guide—with text (slightly edited by me) from two EagleCam monitors—about how to tell the male from the female:

Congowings:
It is easier to see differences when they are both side by side: however, the female is larger than male, including larger feet, bigger beak (upper mandible is deeper & mouth goes back farther under eye). On this particular pair: male has a sleeker look (flatter head when feathers aren’t ruffled), the female’s head appears rounder. When looking close, it almost looks like male has eyeliner on his eyes. I’m sure you see other differences that will help you decide who is who. The male this year has a small black feather on his head. From the back view I have noticed the male seems to cross his flight feathers more and the female’s are more to her sides. When on the nest, the female seems more relaxed and her wings tend to spread away from her body. The male is more alert and is picking at the nest more. His body seems to be more compact.

DeeJay52:
It’s easier to see the differences when they are together on the nest. The female is larger. She has larger rear claw (hallux talon), bigger beak (the upper mandible is deeper and her mouth extends farther under the eye). Dad looks a bit darker than mom. Mom’s head has a more rounded look where dad’s is flatter looking. The male, this year, has a dark feather on the top of his head and also his tail is more square looking while the female has a rounder look. The male’s beak is slightly darker than the female’s.

Here they are together, with the larger female on the right:

And this shows the position of the eye relative to the beak, a diagnostic trait (at least for this pair).  Note the “eyeliner” on the male.

h/t: Diane G

Should we respect the faithful?

February 9, 2011 • 10:12 am

If you’re not regularly reading Greta Christina, you should.  She’s a good writer and a clear, intelligent, and forceful voice for rationality.  Her latest post on AlterNet deals with an issue we’ve all been pondering lately: how much “respect” we should show when dealing with the faithful?  Christina’s answer is clear from her title:  “No, atheists don’t have to show ‘respect’ for religion.”

However, if ecumenicalism were just hypocritical bullshit, I probably wouldn’t care very much. Hypocritical bullshit is all over the human race like a cheap suit. I’m not going to get worked up into a lather every time I see another example of it. So why does this bug me so much?

Well, it also bugs me because — in an irony that would be hilarious if it weren’t so screwed-up — a commitment to ecumenicalism all too often leads to intolerance and hostility toward atheists.

I’ve been in a lot of debates with religious believers over the years. And some of the ugliest, nastiest, most bigoted anti-atheist rhetoric I’ve heard has come from progressive and moderate believers espousing the supposedly tolerant principles of ecumenicalism. I’ve been called a fascist, a zealot, a missionary; I’ve been called hateful, intolerant, close-minded, dogmatic; I’ve been compared to Glenn Beck and Joseph Stalin and Adolph Hitler more times than I can count. All by progressive and moderate believers, who were outraged at the very notion of atheists pointing out the flaws in religious ideas and making an argument that these ideas are probably not true. Progressive and moderate believers who normally are passionate advocates for free expression of ideas will get equally passionate about demanding that atheists shut the hell up. Progressive and moderate believers who normally are all over the idea of diversity and multiculturalism will get intensely defensive of homogeny when one of the voices in the rich cultural tapestry is saying, “I don’t think God exists, and here’s why.” . . .

. . . In my debates and discussions with religious believers, there’s a question I’ve asked many times: “Do you care whether the things you believe are true?” And I’m shocked at how many times I’ve gotten the answer, “No, not really.” It leaves me baffled, practically speechless. (Hey, I said “practically.”) I mean, even leaving out the pragmatic fails and the moral and philosophical bankruptcy of prioritizing pleasantry over reality… isn’t it grossly disrespectful to the God you supposedly believe in? If you really loved God, wouldn’t you want to understand him as best you can? When faced with different ideas about God, wouldn’t you want to ask some questions, and look at the supporting evidence for the different views, and try to figure out which one is probably true? Doesn’t it seem incredibly insulting to God to treat that question as if it didn’t really matter?

Go read the rest; it’s a nice piece.