Why Evolution is True is a blog written by Jerry Coyne, centered on evolution and biology but also dealing with diverse topics like politics, culture, and cats.
Harris aficionados may not find much new on last night’s MSNBC “The Last Word” interview, but it’s not long and he makes a good point about Islam:
There’s no version of Islam which says, “You should be free to criticize the Qur’an: it’s just the product of human minds; the prophet Muhamed was a man like any other man and can be criticized.” There’s no Reform Judaism version of Islam, and we have to encourage one. . . It’s not an accident that we’re not having this conversation about the Amish or Quakers or Jains or even Buddhists.
Ideas have consequences, and the idea that you can get to Paradise by dying in defense of the faith—in fact, dying in defense of the faith is the best thing that can possibly happen to you—that is a mainstream notion in Islam.
Does anyone else’s b.s. detector go off when they hear the mantra, “Islam is a religion of peace”?
Anomalocaris – literally “unusual shrimp” – was first identified in 1892 by Joseph Frederick Whiteaves from mid-Cambrian deposits in British Columbia. It looked pretty much like this fossil, and was thought to look something like the drawing below.
One of the many things that was odd about this “shrimp” is that it never seemed to have a body or a head. All they ever found was the “tail”. There are plenty of these fossils about, and you can pick them up on eBay for a few hundred dollars (not recommended unless you are certain of provenance, that appropriate permission has been obtained, etc).
As is now well known, in 1985 Harry Whittington in Cambridge and Derek Briggs solved the mystery of the missing head of Anomalocaris, and at the same time also clarified the nature of Laggania, which was thought to be a non-descript sponge, and Peytoia, which was seen as a pineapple ring-like jellyfish thing:
They all turned out to be part of the same animal – a vicious predator which is now thought to be related to the arthropods. It still bears the nameAnomalocaris, but what was thought to be the body of the “strange shrimp” is in fact a predatorial claw, while the “legs” are thorny projections. Peytoia is the mouth of Anomalocaris, while Laggania turned out to be its body:
This was part of the Whittington/Briggs/Conway Morris redescription of the Burgess Shale animals which led Stephen Jay Gould to write Wonderful Life, and which is still the source of much debate today. At up to 60 centimetres long,Anomalocaris, and related members of the “great appendage” group are thought to have been the top predators in the Cambrian seas, spearing passing prey with their raptorial claws.
Here’s a nice model of Anomalocaris, from the Manchester Museum:
Here’s a close-up (annoyingly, I couldn’t get to see its mouth) – you can see a Burgess Shale fossil of Waptia below it:
Indeed, these predators are now known to have extended their domination of the seas into the Devonian, as shown by this recently discovered fossil ofSchinderhannes bartelsi from 407 MY ago (Kühl et al. 2009):
Many reconstructions of great appendage predators – and in particular ofAnomalocaris – show them munching away on trilobites. This video from Phleschbubble is particularly striking (Anomalocaris turns up at around 50 seconds. NB the file is pretty large so may take some time to download)
And this great drawing by Sam Gon III shows:
“two Anomalocaris canadensis converging on an Olenoides trilobite. This doesn’t necessarily imply that they engaged in cooperative hunting. The second Anomalocaris could have merely been attracted to the commotion caused by the activities of the other. It would be interesting to consider what kinds of agonistic behaviors occurred between individuals, and whether they engaged in any specialized territorial or courtship behaviors.”
This video (sorry about the music!) not only shows one eating what looks like a trilobite, it also has a pair engaging in either mating or intra-sexual conflict. This is cool but, of course, entirely gratuitous! NB the “streamers” seen on these reconstructions are typical of both Anomalocaris saron and a related anomalocaridid, Amplectobelua symbrachiata:
So, if you believe the videos (and you shouldn’t), the main diet of anomalocaridids would appear to be trilobites. But for the last couple of years Professor “Whitey” Hagadorn of Amherst College has been arguing that the evidence just isn’t there. In 2009 he presented a paper to “Walcott 2009”, a conference to mark the centenary of the discovery of the Burgess Shale deposits, and then three weeks ago he presented more data to the Geological Society of America’s annual meeting.
In an interview with Wired magazine, Hagadorn points out that there’s no direct evidence (e.g. trilobite traces in anomalocaridid guts, or clear anomalocaridid coprolites containing trilobite bits for example), and, as he explains in his 2009 abstract, while the teeth in the mouthparts look pretty sharp (see the picture above):
“Anomalocaridid mouth plates and their tips are never broken, nor are tips worn. If plates were hard, and were used to manipulate, puncture, crush, or masticate biomineralized prey, they would be expected to show evidence of abrasion or breakage. Absence of this evidence is striking given the frequency (0.01-1%) of healed malformations in extant marine arthropods, most of which are due to prey manipulation or feeding. Moreover, anomalocaridid plates and their biting tips are commonly wrinkled, exhibit preburial shearing and tearing, and mantle or are deformed by biomineralized fossils such as brachiopods, trilobites, and Scenella. Plates are preserved as organic carbon and exhibit fracture patterns typical of desiccating arthropod cuticle. Thus anomalocaridid plates, including their tips, were unmineralized and pliable in life.”
Furthermore, in his latest presentation, Hagadorn has made a 3-D reconstruction of the mouth of Anomalocaris and found that not only was the mouth soft, it also couldn’t completely close. So – says Whitey – Anomalocaris and its fellows could do no more than suck nastily on stuff.
I’m neither a paleontologist nor do I do biomechanics, so will find it hard to judge when the data are eventually published (it may be in review, though there’s no trace of it on his website). On the basis of Hagadorn’s talks, opinion for the moment seems to be divided as to whether he is right. That may change when his work is published.
However, let’s assume he is right, and anomalocaridids didn’t eat trilobites. That simply begs the question – who did eat them? Because one thing is certain – those trilobites did get munched by something. There are apparent coprolites (= fossilised turds) that contain trilobite bits, as seen in this picture by Vannier & Chen (2005):
Furthermore, there are plenty of trilobite fossils that have chunks taken out of them, as seen here in this reference to the work of Babcock & Robinson (1989 – taken from my next Evolution of Invertebrates lecture):
The final answer will come, I suppose, when someone finds a clear association between a predator and a consumed trilobite. Until then, studies like that of Whitey Hagardorn are the best we can do.
h/t: Ray Moscow
References and links:
Babcock, L.E. and Robinson, R.A. 1989. Preferences of Palaeozoic predators.Nature, 337, 695-696.
Kühl, G., Briggs D E. G. & Rust J (2009) A great-appendage arthropod with a radial mouth from the Lower Devonian Hunsrück Slate, Germany. Science323:771-773
Vannier J. & Chen J. (2005) Early Cambrian food chain: New evidence from fossil aggregates in the Maotianshan Shale Biota, SW China. Palaios 20:3-26.
Whittington H. B. & Briggs D. E. G. (1985) The largest Cambrian animal,Anomalocaris, Burgess Shale, British Columbia. Philosophical Transactions of the Royal Society of London, Series B, 309, 569-609.
Anomalocaris homepage by Sam Gon III – this contains loads of anatomical and taxonomic information, as well as references, links and reconstructions – a goldmine! This is contained within an excellent website devoted to their apparent prey: trilobites.info
I’m off this morning for the Caribbean coastal town of Cartagena, but it’s sad to leave the delights of Bogotá. It was a wonderful visit, with friendly and hospitable faculty at the Universidad de Los Andes. Here’s a bit of the campus nestled in the verdant Andean foothills.
And a taste of posts to come, including frutas, aves, y ranas. Here’s a hungry (or peeved) Hemiphractus fasciatus:
A special h/t to the U. de l. A. faculty, and my hosts, Andrew Crawford and Vicky Flechas
FINALLY Uncle Karl has finished his “I burn teh strawmenz” series on BioLogos, having exhausted all his arguments against me in the lamest post of all, engagingly titled “Part Six.”
This article is giving me a pain in my lower mesentery, which I can ill afford since I’m on my way to my final dinner in Bogotá, so I’ll just state his arguments briefly. And since they’re self-refuting, I need hardly say more than, “Nice try, Karl, but you didn’t pwn me.”
1. Just like religion, science relies on faith:
Faith plays different roles in different disciplines. The physicist needs no faith to accept the law of the conservation of energy. There is no need for the chemist to have faith in the periodic table. The factual evidence is so great that faith is simply not needed. But evolutionary biology needs some faith. The reconstructions of the history of life on this planet require the postulation of species for which there is no direct evidence. Most of the “common ancestors” are hypothetical in the sense that they have to be constructed indirectly with methods that are far from flawless. I think the evolutionary biologists are doing a great job with this—read Coyne’s excellent Why Evolution is True, if you are skeptical—but the enterprise requires inferences that look very much like little leaps of faith.
I don’t have faith in common ancestors of reptiles and modern birds in the same way that Karl has faith in God. There is tons of real scientific evidence indicating that such ancestors existed, and I anticipate that they, or closely related transitional forms, will be found (many of them have been). There’s no “leap of faith” here. In contrast, belief in God is a leap of faith simply because there’s no credible evidence.
When someone who purports to sell science to religious people starts saying that both magisteria really rest on “faith”, you know that they’re dealing in bad faith.
2. There’s real scientific evidence for Jebus:
Religious reflection is more like economics than it is like chemistry. There is evidence for the claims of the economist and for the chemist and there is evidence for religious truth claims. This is a simple fact. The New Testament contains several documents written about Jesus by smart people in the first century. These documents are evidence.
Yes, just like the Qur’an and the Bhagavad Gita and Urim and Thummim (the golden plates of Moroni) and the writings of L. Ron Hubbard—and all the thousands of religious documents written by smart people purporting to recount real events. Those were also written by smart (or canny) people, and so should count as “evidence” too, no?
One can disagree with the documents and reject the evidence as weak or inadequate in some way. Or one can accept the evidence and be a Christian. But what one cannot do is claim that there is no evidence or dismiss the evidence because it fails to meet the standards of the chemist. If the central claim of Christianity is true—that God became incarnate in Jesus Christ—that is the most complicated and mysterious event in history and the people who tried to articulate what it was like certainly cannot be critiqued because their analyses would not meet the standards of the chemist.
Why not? People are basing their entire lives, and hopes for the afterlife, on what is written by “smart people” in those fictitious documents. Why shouldn’t we require that that evidence at least meet the standards of chemistry? And since Uncle Karl sees so much of the Bible—stuff recounted as if it were as factual as the Resurrection—as simply fictional metaphor, why does he see Jesus’s return to life as “real scientific evidence” while cavalierly dismissing tales like the Flood or Adam and Eve as pretty fictions? Given that nearly the entire Bible is written as if it were true, how does one separate the “evidence” from the pretty stories?
The far more significant difference, of course, relates to the dynamic character of religious investigation. When Isaac Newton “leaped to the conclusion” that gravity ruled the universe, gravity did not respond by embracing Newton and healing his brokenness. When believers make their leap of faith to embrace God, God responds by entering into relationship with believers, often with transformative consequences. There is no counterpart to this response in scientific or historical investigation.
Yes, because religious belief involves fooling oneself while science does not. God doesn’t transform the believers; they believe they’ve been transformed because they’re kidding themselves.
So let’s not disparage the central claims of theology just because they are so much more complicated than the function of penicillin.
Oh, let’s! Those claims really aren’t more complicated than penicillin; they’re just much more ridiculous and much less credible.
It’s been fun, Karl, but can you go after Al Mohler for a while?
Urged on by my Colombian student Daniel, I visited the famous Bogotá snack shop La Puerta Falsa, where, he said, the tamales were “awesome.” It’s a tiny shop in the La Candelaria district, and has been open since 1816! The storefront displays a tempting array of candies:
Temporarily ignoring the sweetmeats, I made myself at home at the tiny counter and ordered a Colombian tamale and a chocolate completa. The tamale is a sticky mass of rice, chicken, and veggies cooked inside a banana leaf. (The Chinese have a similar rice-and-meat combination steamed inside a taro leaf.) And it is indeed awesome.
I had the chocolate for dessert. Colombian chocolate is often served with cheese, which I guess some folks actually put into the chocolate to melt. I preferred it on the side, with buttered bread and a bun. It was luscious, not goopy thick like Mexican hot chocolate but rich and spicy:
Total bill for this belly-busting meal: about $5. And for another dollar I picked up two of those candies—a peanut praline and a coconut disk. Each was about four inches across:
If you find yourself of good appetite in Bogotá, get yourself to La Puerta Falsa.
Perhaps the most famous tourist site in Bogotá is the Museo del Oro—the Gold Museum. With more than 55,000 pieces, it’s the world’s largest collection of native American gold objects.
I went two days ago, but went a bit jaded, thinking, “How good can this really be?” Well, it’s really good—fantastic, in fact—and I spent three hours wandering around and taking photographs. I could easily have stayed for a few more hours.
What I’d like to do in this post is simply show some of the animals, a small subset of all the objects on display (I may show some other stuff later). I don’t have dates for most of these, because they weren’t given, but these are all pre-Hispanic, with some going back three thousand years. You can see a short video here.
Now, los animales. First, a beautiful gold flying fish. (Click on all pictures to enlarge them.)
And what was described as a catfish:
A caiman:
Some frogs:
Insects:
Three beautiful birds (the first is dated):
A vulture:
Bats (hanging upside down):
A jaguar mask (jaguars were of immense symbolic importance in many Mesoamerican cultures):
And finally, some unidentified animals. Your guess is as good as mine:
