Tuesday, March 31, 2009

Another Anomalocaris

ResearchBlogging.org
I don’t know! You wait ages for a new Anomalocarid, then two come by in close succession! First Schinderhannes bartelsi and now Hurdia.

Yes . . . well . . . another Anomalocarid,

Another weird Anomalocarid.

Allison C. Daley, Graham E. Budd, Jean-Bernard Caron, Gregory D. Edgecombe,, & Desmond Collins (2009). The Burgess Shale Anomalocaridid Hurdia and Its Significance for Early Euarthropod Evolution. Science, 1597-1600 DOI: 10.1126/science.1169514

Where to start! When I first saw it, I thought is was an Anomalocarid caught in flagrante delicto with a phyllocarid!

This is a bit of déjà vu, as with the original identification of Anomalocaris from the Burgess Shale, here’s another case of a number of isolated fragments being found previously (mouthparts, frontal appendages, body, and those weird frontal carapaces - a total of 8 Cambrian taxa) and given separate names, now being brought together into one complete specimen – just like the original Anomalocaris.

While the body, eyes and great appendages are similar to other Anomalocarids, the major difference here is the strange, and very large, carapace or shield-like structure on the head.

It is unlike any other Anomalocarid, with the possible exception of S. bartelsi which has a structure at the back of the head, which may be a funky posterior-flaring carapace-like structure (although that structure could be a pair of trunk appendages).

Fig. 2. Paratype specimen and isolated components of H. victoria. (A) ROM 49930, paratype, lateral view showing lateral flaps. (B) ROM 59258, frontal appendage morph A. (C) ROM 59259, frontal appendage morph B. (D) ROM 59260, mouthpart with extra teeth rows. (E) ROM 59261, lanceolate gill blades showing attachment at one end (arrow). (F) ROM 59262, paired P-elements. (G) USNM 57718, holotype of H. victoria. Scale bars, 1 cm. Abbreviations are as in Fig. 1. B, Banffia; ex, extra teeth rows.

Firstly the head. This is by far the most bizarre Anomalocarid, by virtue of the head, which is the first Anomalocarid identified with a carapace. At almost 50% of the length of the animal, it's huge, and made of two different "elements", a single “H” element and a paired “P” element. There doesn’t appear to be anything below this carapace, so it’s function is something of a mystery.

Why on earth is it there?!

Sexual selection maybe?
There are certainly examples of other arthropods that have an exaggerated body part used to attract a mate – think of the fiddler crab, but all seven fully articulated (with all the bits in the right place) specimens show this remarkable carapace, and it’s unlikely that all seven would be all one sex (if the structure was confined to one sex). Although it would be interesting to see if the size of the carapaces shows any bimodal distribution which may indicate a size differential, possibly based on sex. But as arthropods generally keep growing, maybe there are two sets of growth trends.

Prey capture maybe?
Perhaps Hurdia trapped small prey below the carapace and then advanced so that the appendages could grasp the prey. Or maybe it was used to dig into soft sediment after prey. Or perhaps it contained sensing apparatus to detect prey in the sediment

Who knows?

The rest of the beast conforms pretty much to the standard Anomalocarid body plan, including the circular jaws. This time, however, there are more teeth just for added effect.

Hurdia does have a fine set of gills though. And they appear to be free hanging gill structures, and similar to crustacean and chelicerate gill structures, rather than the modern arthropod biramous limb (where the leg and the gill are part of the same structure). This is interesting because it is thought that the Cambrian arthropod biramous limb formed by the fusion of a uniramous leg (just the leg) and a respiratory exite (gill), whereas the modern biramous limb is formed by a split of the main axis of the limb. The presence of separate filamentous gills in Cambrian Anomalocarids pushes the structure below the crown group arthropods and into the stem group arthropods, supporting the fusion theory.

An analysis groups Hurdia along with Anomalocaris and Laggania as a sister group, outside of the Euarthropods, or crown group arthropods.

Schinderhannes bartelsi fits in between Hurdia and Fuxianhuia.

Incidentally the reconstruction of Hurdia was done by Merrianne Collins, who did the reconstructions for Steve Gould's book on the Burgess Shale fossils, "Wonderful Life".

Allison C. Daley, Graham E. Budd, Jean-Bernard Caron, Gregory D. Edgecombe,, & Desmond Collins (2009). The Burgess Shale Anomalocaridid Hurdia and Its Significance for Early Euarthropod Evolution. Science, 1597-1600 DOI: 10.1126/science.1169514

Sunday, March 22, 2009

New Scientist - It just gets worse

Having put out a highly misleading cover and story claiming that "Darwin was wrong" when in fact Darwin never discussed the topic, and the tree of life is still very much a solid analogy for metazoan evolution, New Scientist just can't let a bad decision go.

They now have that cover on an adverting poster.

Having antagonised a lot of scientists with their cheap sensationalism to generate sales, re-using the cover is simply giving the finger and saying 'we don't care about accuracy, sales are the thing'.

Jerry Coyne is calling for a boycott, PZ agrees. So do I.

But it should also be a science boycott. High profile scientists who contribute to NS should refuse to continue to do so. Scientists who are approached for stories should refuse to cooperate and make sure the editors know the reason. Tell the reporter why, and ask that the reporter tell the editors the reason why.

But there is another thing scientists can do, and that is assist other science publications such as Discover, and Seed with contributions. If these publications can get a series of high profile stories, the circulation of these publications will rise. That way then the science message can get out, while snubbing NS.

If I were an editor of Discover or Seed, I'd be on the phone to some leading scientists now, to line up some contributions.

Saturday, March 21, 2009

Anti-Science Science Minister?

The recent statements by the Canadian Minister for Science have left the impression that he does not understand evolution and he does not accept evolution. The reason? When asked about whether he believed in evolution, he refused to answer saying that is was a religious question.

Actually, I have to say that, in part, he is right. I do not believe in evolution. I accept evolution is one of strongest scientific theories we have, because of the overwhelming scientific evidence that supports it, from a myriad of scientific disciplines. I do not believe in evolution. Belief is a religious question.

However, the Minister clearly wasn't talking about that when, in his response, he conflated evolution and religion. That, frankly, is a creationist response. His subsequent clarification also showed that he doesn't understand evolution.

As a consequence, he has been tagged, with justification, as anti-science.

So? After all, there is no requirement that the Minister for Science has to be a scientist, or accept one of the fundamental basics of modern science?

Well, having a science minister who doesn't accept one of the fundamental basics of modern science, is like having a health minister who doesn't accept that HIV causes Aids. Wait a miniute, we've had one of those in South Africa.

How did that turn out?

Umm, not well.

Thursday, March 19, 2009

Oklahoma legislator admits human life does not start at conception

Mike Reynolds, an anti-stem cell research, anti-abortion, Christian fundamentalist, Republican (though you guessed that last one, right?) in the Oklahoma State legislature, has introduced a bill to thwart President Obama's removal of Bush's restrictions on stem cell research.

In part Bill 1326 reads, in part:
B. No person shall:
1. Knowingly conduct nontherapeutic research that destroys a human embryo or subjects a human embryo to substantial risk of injury or death;
2. Transfer a human embryo with the knowledge that the embryo will be subjected to nontherapeutic research; or
3. Use for research purposes cells or tissues that the person knows were obtained by performing activities in violation of this section.
C. Any person or any business entity recognized by the laws of this state that engages in, or is associated with a business entity that engages in, the actions prohibited by subsection B of this section shall not be eligible for any Oklahoma income tax credits. No state agency or retirement system shall invest in a business entity that engages in the acts prohibited by subsection B of this section.
D. Any person found violating the provisions of subsection B of this section shall, upon conviction, be guilty of a misdemeanor.
But wait a minute. Anyone that destroys a human or subjects a human to substantial risk of injury or death, would attract for more substantial penalties than a misdemeanor. Therefore, it logically follows that Reynolds does not consider an embryo as human, and that, therefore, human life does not start at conception!

Does his constituents, and more importantly, his parishioners (yes, he is an Ordained Deacon) know his views on when life starts?!

More at ERV.

Religious Ghouls - Pope Lies (Shock, Horror)

Ratzinger's brave new world apparently now includes bald-faced lying.

In comments that have been reported widely, Ratzinger, on his way to Camaroon, said that HIV/AIDS
was a tragedy that cannot be overcome by money alone, that cannot be overcome through the distribution of condoms, which can even increase the problem.
That's a flat out lie, see here, here, the FDA, the Center for Disease Control, and how about the UNAIDS Position Statement on Condoms and HIV Prevention, July 2004, which says in part:
The male latex condom is the single, most efficient, available technology to reduce the sexual transmission of HIV and other sexually transmitted infections.
If he had stopped at "was a tragedy that cannot be overcome by money alone, that cannot be overcome through the distribution of condoms", then he would have been on safer ground. HIV/AIDS cannot be overcome by money alone, nor through the distribution of condoms alone. HIV/AIDS needs a multidisciplined approach that includes education, treatment and prevention. But Ratzinger couldn't resist the opportunity to lie.

He's supposed to be a 'fisher of men'. What kind of catch do you get with bait like that?

Never forget these people want to control female reproductive rights.

Tuesday, March 17, 2009

Red Dwarf - Update

The British cable channel "Dave" has released the schedule for the 3 new episodes of Red Dwarf, "Back to Earth parts I, II, and III. The will be shown each night from Friday April 10 at 9.00pm, along with other classic episodes and a "Making Of" documentary, and finally all three episodes and the "Making Of" together on April 13.

Friday, April 10th from 9pm
Back to Earth - Part One
Gunmen of the Apocalypse
Quarantine
Tikka to Ride

Saturday, April 11th from 9pm
Back to Earth - Part Two
Smeg Ups
Polymorph
Emohawk - Polymorph II

Sunday, April 12th from 9pm
Back to Earth - Part Three
The Making of Back to Earth
Back to Reality
Marooned

Monday, April 13th from 9pm
Back to Earth - Part One
Back to Earth - Part Two
Back to Earth - Part Three
The Making of Back to Earth

If, like me you can't make the UK in April, there is even better news. The DVD of all three episodes, plus the documentary and additional content, is scheduled for release on July 15th

Sunday, March 15, 2009

Now THAT'S a spacecraft

Finally! A cool looking spacecraft.

The European Space Agency's Gose satellite is due to be launched from the Plesetsk Cosmodrome in north-west Russia on Monday.

But just look at it!

It's beautiful.

It's what a space vehicle should look like. It's got an ion engine. It's even got FINS!

The Goce satellite will measure tiny variations in the pull of gravity experienced across the planet.

The fact that the Earth is not a perfect sphere, but is flattened at the poles, and as the composition of the Earth varies from place to place (varying the density), results in a variable density, which in turn varies the pull of gravity.

As the measurements are so small, Goce must fly very low, 270km, which means that it will interact with the slight atmosphere still present at that height. Hence the fins.

It also has a cool xenon ion propultion system to ensure smooth flight through the traces of amosphere.

NASA? Are you watching? Next time you put a sattelite up, at least shove some fins on it!

Full story at the BBC.

More info on Gose can be found on the European Space Agency site. Including this cool video.

Saturday, March 14, 2009

Addicted to Adduction

The inability of creationists to deal honestly with scientific evidence is legendary, especially when it comes to human evolution. Answers in Genesis and the Institute for Creation Science are the standard bearers of disingenuity.

Jim Foley has a post up at the Panda's Thumb about the latest creationist effort, this time concerning the recent find of 1.5 million year old fossil footprints from Illeret, Keyna.

One thing caught my attention was a neat story concerning the hallux, or big toe.

Discussing the different characteristics of modern, Illeret and Laetoli footprints (and hence exposing the claims by creationists that they are all the same, and so human), Jim mentions the hallux and abduction. Abduction of the hallux can be explained as the 'movement' of the hallux away from the line of the foot.

Compare your left hand and foot. Draw an imaginary line through the length of the foot. The hallux is set slightly off that line (taking in to account changes to the big toe caused by a lifetime of wearing shoes). Now, compare that the your left hand. The thumb is at a much greater angle to a line along the length of the hand. The thumb is abducted to a much greater extent that the hallux.

The foot of our distant ancestors would have had been more like our hand in terms of the position of the hallux - for prehensile reasons. But as our ancestors moved to be primarily ground dwellers and upright bipedalists, the shape of the foot evolved. The big toe adducted (moved closer the the line of the foot - the opposite of abducted) and the footprints at Illeret and Laetoli show this rather neatly.

The angle of abduction in modern humans is around 8 degrees (see figure showing abduction angle for the left foot). The angle of abduction of the Laetoli prints (at 3.7 mya) is 27 degrees. The angle of abduction for the Illeret prints (at 1.5 mya) falls neatly in between these two values at 14 degrees.

Now, what is another name for something that falls somewhere between two conditions? . . . Umm . . . Oh yeah, . . . intermediary.

Tuesday, March 10, 2009

Palaeoporn 11 - again


OK, back by huge public demand . . . err of one. Palaeoporn 11 is back with mark-ups.

The photo is of a portion of an Anomalocaris appendage, and shows the typical preservation style of fossils in the Emu Bay Shale.

In the photo (click to enlarge) there are three segments (S) and two segment boundaries (SB) the segment boundary is doubled because the original appendage was roughly circular, and when you flatten a tube, you don't get the appendage boundary matching up when squashed.

The specimen has been re-crystallised during an episode of overthrusting. The surface of the fossil is normal calcite, but in the centre the calicite is in the a fibrous form (FC). The matrix where the fossil was, is smooth (M2), the normal matrix is M1.

There is no phosphatisation of muscle tissue, and so this is probably a moult. But that's another story . . .

Sunday, March 8, 2009

Palaeoporn 11



A slightly different Palaeoporn this time, as there's a bit of a theme this week, on preservation. A bit later I'll be discussing how to fossilise muscle tissue. This, and other specimens helped in coming up with the process.

This is a fragment of an Anomalocaris appendage from the Cambrian Emu Bay Shale. The interesting thing is the preservation. The outer layer preserves the impression of the appendage, together with segment boundaries. Inside, is a layer of fibrous calcite crystals. The specimen has been re-crystallised after a metamorphic event which included overthrusting. The crystals are, in fact aligned to the stress field, as they 'lean' towards the north - the thrust direction was south to north.

Religious Ghouls - update

Apparently the excommunication has occurred.

The Vatican approves.

Welcome to Ratzinger's brave new world. After controlling the Papacy for the last years of the previous Pope, while Karol Wojtyla was, literally, a drooling idiot, Ratzinger successfully entrenched the fundamentalist's in power behind the scenes. His elevation to the Papacy has simply allowed him to consolidate a new fundamentalist catholic church.

Back come members of the fundamentalist cult of Saint Pius X, previously excommunicated (never mine the holocaust deniers). Ghouls like Sobrinho excommunicate people for trying to protect the life of a 9 year old girl, and the Vatican approves. But does not excommunicate the serial rapist of little girls, and the Vatican approves.

Never forget that these people want to control female reproductive rights.

Friday, March 6, 2009

Religious Ghoul

There is a terrible case in Brazil of a 9 year old girl raped by her stepfather since she was 6, who became pregnant with twins.

The Archbishop of Olinda and Recife, Jose Cardoso Sobrinho has waded into this situation with the promise of excommunication.

That's OK. The rapist deserves it (if you are threatened by that sort of thing).

Well, actually, no.

The Archbishop of Olinda and Recife has promised to excommunicate the mother and the doctors that treated the child! Why? Because they performed an abortion.

In Brazil, abortion is legal for rape victims, and also where the life of the woman is under threat. The doctors who treated the child considered that she complied with both conditions, for, at only 9 years old, they considered that her uterus was too small to carry one baby to term, let alone twins.

Apparently repeatedly raping a child since she was 6 is not an excommunication offense. Raping her older intellectually challenged sister (now aged 14) is not an excommunication offense. Saving a 9 year old girl is an excommunication offense.

The reason for the mother and the doctor's actions - the health of a 9 year old girl.

The reason for the Bishop's actions - he's a Catholic priest . . . oh yeah, and because he's a ghoul.

Never forget these people want to control woman's reproductive rights.

Monday, March 2, 2009

10,000th visit

My Statview counter had just clicked over the 10,000th visit. Not bad considering I only put it in on December 10th.

And the winner is . . .


View Larger Map

Someone from (or using a internet provider from) Morgantown, West Virginia. Whoever it was logged on using Comcast Cable using an IP address of 71.206.*** So whoever you are, hi and thanks for stopping by again. Feel free to say hi if you want too (here, or by email).

Morgantown has a population of just over 23,000 and is the home of West Virgina University (go Mountaineers!)

Sunday, March 1, 2009

Touring with Mr. Darwin

I've been meaning to blog this for a while, but have been too busy. I went to see the exhibition on Darwin at the National Museum of Australia, here in Canberra. It's good. It's very good!

The exhibits cover the world before Darwin, the young Darwin, the Beagle trip, the development of the theory, the theory and aftermath, and evolution today.

It's not large exhibition, but it does cram a fair amount in. The displays include writings, specimens, a mock up of Darwin's study, and AV displays - including three short films featuring evolutionary scientists such as Francisco Ayala, Francis Collins, Niles Eldredge, and Kenneth Miller. They also feature Genie Scott from the NCSE (join the NCSE today).

By far the most impressive pieces (and worth the price of admission on their own), are the writings of Darwin - notebook entries, manuscript pages and letters. Not copies, the real thing, pages, hand-written by Darwin himself. And not only from Darwin, there were letters from Hooker, FitzRoy, Wallace, and one from Huxley - that features the famous lines,
As for your doctrines I am prepared to go to the Stake if requisite... I trust you will not allow yourself to be in any way disgusted or annoyed by the considerable abuse & misrepresentation which unless I greatly mistake is in store for you... And as to the curs which will bark and yelp - you must recollect that some of your friends at any rate are endowed with an amount of combativeness which (though you have often & justly rebuked it) may stand you in good stead - I am sharpening up my claws and beak in readiness.
It's sad that, after 150 years, the curs still bark and yelp, but it's good to see that Darwin still has friends endowed with an amount of combativeness.

There were also family letters by Darwin, Emma Darwin, and Darwin's father.

The imagery and linkage they provoked was so palpable, it was almost like being in the room when they were written. I got positively goose-bumpy.

The highlight for me though, was the actual notebook, open to the page with the famous I think evolutionary tree (right). The actual notebook!

Wow! Like. Wow!

It's a good job it was in a plastic display case, because I think I was drooling à la Homer Simpson! To be so close to an image right out of the pages (literally) of science history!

The notebooks were amazingly small, no more that around 15 cms by 7 cms.

Interesting fact: Darwin wrote over 300 notebook pages on animals and plants, but over 1300 on geology.

One of the largest displays was a reconstruction of Darwin's study in Down House. This was very well done, and you almost expected Darwin to walk into the room at any moment! Quite poignant, was a shawl draped over the chair in the corner of the study. Late in life many images of Darwin have him wearing such a shawl.

This exhibit also had a brief description of Darwin's daily schedule, including his early morning walks around the Sandwalk - the walk behind Down House that Darwin used almost every day.

There was also a video of the Sandwalk, composed of still photos taken at 5 metre intervals all the way around the Sandwalk. So I took a stroll. I didn't see Larry Moran there though!

Interesting fact: only some 80 pages of the Origin manuscript survive. Darwin gave many of the manuscript pages to the children so that they could use the blank side to draw on!

The section on evolution today also carried the theme of controversy from when the Origin was released to the present. There was a short video describing the difference in use of the term 'theory' in science compared with everyday use. Genie Scott was front and centre again, along with a number of other scientists.

I noticed that, with the exception of Genie and Francisco Ayala (who could be dragged through a hedge backwards and still look elegant), there was a certain amount lacking in the dress sense department. Richard Fortey did look he'd just been pulled through a hedge backwards, and Niles Eldredge looked like he'd borrowed somebody else's suit! However, that really didn't matter, because science places more importance in substance than style, whereas ID creationism places style over substance - because they have no substance.

There was some coverage of ID creationism in the section on evolution today. It included an actual disclaimer
from Cobb County Georgia,
This textbook contains material on evolution. Evolution is a theory, not a fact, regarding the origin of living things. This material should be approached with an open mind, studied carefully and critically considered.
I have to say it was much more disturbing in the flesh. Of course I've been aware of such disclaimers, and the litany of failures they have had in court, but to see one up close made it somehow more real, and not just something that was happening a long way away (even more reason to join the NCSE today).

All up, an excellent way to spend a couple of hours, and highly recommended.

Darwin is at the National Museum of Australia until the 29th of March.