NASA sure does know how to drag out the kooks. NASA's innovative new project for studying the Moon's chemistry and attempting to detect water involves effectively slamming a projectile into the Moon's surface and analyzing the resulting ejecta. The Register reports on the crazies who are concerned about the US government's latest 'bombing campaign':
He wasn't alone, either, with various observers backing the surrealists' possible belief that NASA might inadvertently cause major havoc with their crater strike. This might seem to be impossible given the bigness of the Moon, the smallness of the LCROSS, and the laws of physics - but there were those who disagreed. Commentard Greenstar perhaps summed up this point of view best:
Think of the planets in terms of forming a sentence. The Earth is a noun. The moon is a verb. Its very existance creates action in the tides, the weather, and possibly human mood. It's perfection of rotation sets into play all the components that make it possible for life here to exist and yet no life exists there. How is that possible? Wouldn't it seem logical for the earth to have a reciprocal effect on the moon - but it doesn't. The laws of symbiosis don't apply. If the moon is nothing more than a big rock then it can be cleaved like a big rock. Laws of mass and density don't apply nor do they offer us protection from the idiots at NASA who have never watched a diamond cutter. They are big boys with BIG toys and brains the size of a TRex AND are running the risk of making us all extinct.
In the meantime. The reality-based community can follow the LCROSS project at NASA's LCROSS website
Larry Moran Ardipithecus ramidus
Larry Moran has a good piece about the newest fossil hominid find, Ardipithecus ramidus. He goes after some of the irresponsible reportage from both the journalists and scientists alike. Having dealt with the sometimes difficult task of explaining the significance of certain new fossils to journalists, I can understand that sometimes things would get lost in translation. However, here we have an example of highly problematic statements coming from both scientists and the media.
I've got a lot on my plate this week, but I would like to write a comment or two about Ardipithecus this week. Hopefully I'll have that up soon.
I've got a lot on my plate this week, but I would like to write a comment or two about Ardipithecus this week. Hopefully I'll have that up soon.
Dr. Gans
Carl Gans, a giant in the field of comparative and functional morphology, has died at 86.
Dr. Gans has left a profound and lasting impact on vertebrate anatomy and evolution. His work with Glenn Northcutt laid foundations for modern ideas on the role of neural crest in the evolution of the vertebrate head. He was the editor of the 23-volume Biology of the Reptilia, a remarkable source of ideas and data on reptile biology and evolution.
Obituaries: NY Times; CNAH
Tip to Palaeoblog
MacBook Pro
This was a frustrating and disappointing part of my day:
After lunch, I opened my year-old MacBook Pro from its slumber to find a nice set of off-center racing stripes down my screen. Turns out, they go away if I jostle the monitor panel a bit, but that's not going to cut it. The vertical lines will reappear and continue to remind me of the cheap and overrated engineering.
I'm very disappointed by this. My options right now are either to pay to get it fixed or pay to get a new computer. I can't stand the thought of going back to Windows, really. However, the thought of giving Apple another cent of my money is really putting me off. This one forum thread alone can regale you with 12 pages of anecdotes about this same problem with MacBook Pros. Even while under warranty, some folks have gone through three or more new computers—or so the stories say.
UPDATE: Apple has kindly offered to cover the costs of the repair. It's still rather disappointing though.
After lunch, I opened my year-old MacBook Pro from its slumber to find a nice set of off-center racing stripes down my screen. Turns out, they go away if I jostle the monitor panel a bit, but that's not going to cut it. The vertical lines will reappear and continue to remind me of the cheap and overrated engineering.
I'm very disappointed by this. My options right now are either to pay to get it fixed or pay to get a new computer. I can't stand the thought of going back to Windows, really. However, the thought of giving Apple another cent of my money is really putting me off. This one forum thread alone can regale you with 12 pages of anecdotes about this same problem with MacBook Pros. Even while under warranty, some folks have gone through three or more new computers—or so the stories say.
UPDATE: Apple has kindly offered to cover the costs of the repair. It's still rather disappointing though.
the anti-vaccination crowd
It looks like the anti-vaccination crowd is starting to have the effect they want on public opinion. This article is not very encouraging.
At the same time, I'm a bit encouraged by the reporting in that article. I does not give any credible space to antivax lunatics. It does look to the 'other side' of the question of the H1N1 vaccines (or flu vaccines in general), by considering the opinions given by a team of university-based researchers—not Bill Maher, Jenny McCarthy, or Jim Carrey.
The opinions of these wack-o Hollywood types are winning the battle of public opinion, however, and more of this type of reporting is going to be needed. The article also has a list of figures at the end which, I think, also helps mitigate some of the over-the-top media hype about this flu, while providing evidence against the unfounded claims about the dangers of this new vaccine.
"I don't believe in the flu shot," said a typical posting on a Canadian news website this week, which went on to suggest the vaccine could have the same effects on pregnant women as Thalidomide. "I refuse to be a guinea pig."
An Ipsos Reid survey for Canwest News Service released yesterday suggested that barely half of Canadians were even somewhat likely to get the shot.
At the same time, I'm a bit encouraged by the reporting in that article. I does not give any credible space to antivax lunatics. It does look to the 'other side' of the question of the H1N1 vaccines (or flu vaccines in general), by considering the opinions given by a team of university-based researchers—not Bill Maher, Jenny McCarthy, or Jim Carrey.
The opinions of these wack-o Hollywood types are winning the battle of public opinion, however, and more of this type of reporting is going to be needed. The article also has a list of figures at the end which, I think, also helps mitigate some of the over-the-top media hype about this flu, while providing evidence against the unfounded claims about the dangers of this new vaccine.
Maybe some redemption can be found in parody.
This review, and all seven subsequent parts made my day.
the University's statement on the event
I was much dismayed to learn that Ann Coulter was going to speak at the University of Ottawa. I was even more dismayed to find that the U of O provost sent her a letter warning her of the consequences of hate speech. However, I'm shocked and ashamed that her talk has been cancelled citing "security reasons". The real reason seems to be a response to the 2,000 angry protesters on campus. I support the protesters, but I also support Ann Coulter's right to speak—even if I find what she has to say bigoted, vile, and contemptible.
In the first instance, I don't think she should have been invited to speak at the U of O at all. While I'm not a conservative, I grant that there are probably countless other conservatives with far more scholarly and worthwhile opinions than Coulter. Coulter is the Howard Stern of political punditry, and the more shocking and offensive her remarks the more she thrives. After all, each time she spouts one of her racist, homophobic, or xenophobic slurs, her name rockets up to the top of the headlines. There is all of zero intellectual content in what she has to say. Nonetheless, she had been invited to speak and the attempt to un-do the mistake is simply a farce.
On a university campus, the way to handle cases like Ann Coulter is pretty simple: pack the audience and ask questions at the end. The stage is as much a platform for her to speak as it is one for her to receive the brunt of criticism and questioning of her dispicable views. Universities are marketplaces of ideas, and there's no doubt that there are enough well-informed, intelligent people there who can handle Coulter's hateful rhetoric.
UPDATE: The news now is that it was the organizers themselves, not the university who pulled the plug on this event. Like several other bloggers and columnists, I was quick to pour scorn on the U of O.
Here's the University's statement on the event:
Nevertheless, Coulter is still playing her martyr card, and Faux News, I'm sure, is crowing right along with her.
h/t to tom for pointing this out in the comments. Thanks!
In the first instance, I don't think she should have been invited to speak at the U of O at all. While I'm not a conservative, I grant that there are probably countless other conservatives with far more scholarly and worthwhile opinions than Coulter. Coulter is the Howard Stern of political punditry, and the more shocking and offensive her remarks the more she thrives. After all, each time she spouts one of her racist, homophobic, or xenophobic slurs, her name rockets up to the top of the headlines. There is all of zero intellectual content in what she has to say. Nonetheless, she had been invited to speak and the attempt to un-do the mistake is simply a farce.
On a university campus, the way to handle cases like Ann Coulter is pretty simple: pack the audience and ask questions at the end. The stage is as much a platform for her to speak as it is one for her to receive the brunt of criticism and questioning of her dispicable views. Universities are marketplaces of ideas, and there's no doubt that there are enough well-informed, intelligent people there who can handle Coulter's hateful rhetoric.
UPDATE: The news now is that it was the organizers themselves, not the university who pulled the plug on this event. Like several other bloggers and columnists, I was quick to pour scorn on the U of O.
Here's the University's statement on the event:
Dear Alumni and Friends,
On Tuesday, March 23, an appearance by Ann Coulter was scheduled on our campus, organized by the International Free Press Society Canada and the Clare Boothe Luce Policy Institute.
The University of Ottawa has always promoted and defended freedom of expression. For that reason, we did not at any time oppose Ann Coulter’s appearance. Whether it is Ann Coulter or any other speaker, diverse views have always been and continue to be welcome on our campus.
Last night, the organizers themselves decided at 7:50 p.m. to cancel the event and so informed the University’s Protection Services staff on site. At that time, a crowd of about one thousand people had peacefully gathered at Marion Hall.
"Freedom of expression is a core value that the University of Ottawa has always promoted," said Allan Rock, President of the University. "We have a long history of hosting contentious and controversial speakers on our campus. Last night was no exception, as people gathered here to listen to and debate Ann Coulter’s opinions.
I encourage our students, faculty and other members of our community to maintain our University as an open forum for diverse opinions. Ours is a safe and democratic environment for the expression of views, and we will keep it that way."
Nevertheless, Coulter is still playing her martyr card, and Faux News, I'm sure, is crowing right along with her.
h/t to tom for pointing this out in the comments. Thanks!
Stem groups' of extinct clades
The notion of a 'stem group' is indespensible for a palaeontologist. Much used and abused, it is simply not possible to talk about the relationships of fossils to modern life without the use of the crown and stem group concepts. The crown group is a clade which is delimited by its living (extant) members. The stem group comprises those fossils which are closer to the crown group than to any other extant clade, but do not fall within the crown group. As a result, the stem group is paraphyletic, and thus not really a group at all. It is perhaps more useful to talk about a 'stem assemblage' than a 'stem group'.
While at this year's SVP (and at previous meetings), I was struck by some of the terminological abuses of the term 'stem group'. In various instances, it was used either to refer to the nearest sister taxa of an extinct clade, or it appealed to essentialist nomenclature. I comment further on these below the fold.
'Stem groups' of extinct clades:
When a clade is extinct is has neither a crown nor a stem. If we did not distinguish between extant and extinct clades when applying the crown group concept, then crown groups could be arbitrarily small and stem groups arbitrarily deep. Because nodes in a cladogram are rotatable, we could use any taxon (fossil or living) to be a stem taxon.
We already have a set of terms for this: sister group relationships. This is also what the crown group concept conveys. However, it's purpose is to convey the relationship of fossils to a particular living group. When we talk about fossil or extant clades, we can talk about the nearest sister taxa. When talking about fossils in relation to an extant clade, only then do we apply the crown group concept.
Arbitrarily deep stem groups
One abstract title at this year's meeting struck me, because it referred to the fossil Morganucodon as the earliest stem-mammal. This taxon is almost certainly a stem-mammal. Is it the earliest? Take a look at this figure (from Angielczyk, 2009) (you may have to click on it to see the full image):
Notice the placement of the node "Mammalia". It's a full two internodes displaced from the node that subtends the extant mammalian branches: monotremes, marsupials, and placentals. You'll also notice that the Triassic fossil Morganucodon is the nearest fossil sister group of the three extant mammal lineages. In other words, it's the nearest sister taxon (in this tree) of the mammalian crown group (which, strangely, is unnamed!).
This is a peculiar trait among palaeontologists: give the standard crown group name (i.e Mammalia, Aves, etc.) to some arbitrary node within the group's stem. For instance, Aves (birds) is often considered to be the clade delimited by the last common ancestor of all extant birds + Archaeopteryx.
What you should also notice in the diagram above is that the root node of this tree is called "Synapsida". This means it entire run of taxa in this tree from the Synapsida node up to (but not including) the unnamed mammalian crown group nodes are part of the mammalian stem assemblage. Yes, Dimetrodon is a stem mammal, as well as Morganucodon. This means that a host of Permian (and potentially earlier) forms are also stem mammals, leaving Morganucodon appearing fairly late in the game.
The utility of the stem/crown group concept comes in placing fossils in relation to living groups. When we do this, fossils can be used to build up knowledge of the sequence of acquisition of homologies where living forms provide no clues. Fossils can, in turn, help test hypotheses of homology by providing unexpected combinations of characters, as well as precluding or 'predicting' certain character combinations. It is important that these concepts are applied in the correct fashion, or else they (and fossils) will lose their meaning.
Angielczyk, K. 2009. Dimetrodon Is Not a Dinosaur: Using Tree Thinking to Understand the Ancient Relatives of Mammals and their Evolution. Evolution: Education & Outreach 2:257–271.
While at this year's SVP (and at previous meetings), I was struck by some of the terminological abuses of the term 'stem group'. In various instances, it was used either to refer to the nearest sister taxa of an extinct clade, or it appealed to essentialist nomenclature. I comment further on these below the fold.
'Stem groups' of extinct clades:
When a clade is extinct is has neither a crown nor a stem. If we did not distinguish between extant and extinct clades when applying the crown group concept, then crown groups could be arbitrarily small and stem groups arbitrarily deep. Because nodes in a cladogram are rotatable, we could use any taxon (fossil or living) to be a stem taxon.
We already have a set of terms for this: sister group relationships. This is also what the crown group concept conveys. However, it's purpose is to convey the relationship of fossils to a particular living group. When we talk about fossil or extant clades, we can talk about the nearest sister taxa. When talking about fossils in relation to an extant clade, only then do we apply the crown group concept.
Arbitrarily deep stem groups
One abstract title at this year's meeting struck me, because it referred to the fossil Morganucodon as the earliest stem-mammal. This taxon is almost certainly a stem-mammal. Is it the earliest? Take a look at this figure (from Angielczyk, 2009) (you may have to click on it to see the full image):
Notice the placement of the node "Mammalia". It's a full two internodes displaced from the node that subtends the extant mammalian branches: monotremes, marsupials, and placentals. You'll also notice that the Triassic fossil Morganucodon is the nearest fossil sister group of the three extant mammal lineages. In other words, it's the nearest sister taxon (in this tree) of the mammalian crown group (which, strangely, is unnamed!).
This is a peculiar trait among palaeontologists: give the standard crown group name (i.e Mammalia, Aves, etc.) to some arbitrary node within the group's stem. For instance, Aves (birds) is often considered to be the clade delimited by the last common ancestor of all extant birds + Archaeopteryx.
What you should also notice in the diagram above is that the root node of this tree is called "Synapsida". This means it entire run of taxa in this tree from the Synapsida node up to (but not including) the unnamed mammalian crown group nodes are part of the mammalian stem assemblage. Yes, Dimetrodon is a stem mammal, as well as Morganucodon. This means that a host of Permian (and potentially earlier) forms are also stem mammals, leaving Morganucodon appearing fairly late in the game.
The utility of the stem/crown group concept comes in placing fossils in relation to living groups. When we do this, fossils can be used to build up knowledge of the sequence of acquisition of homologies where living forms provide no clues. Fossils can, in turn, help test hypotheses of homology by providing unexpected combinations of characters, as well as precluding or 'predicting' certain character combinations. It is important that these concepts are applied in the correct fashion, or else they (and fossils) will lose their meaning.
Angielczyk, K. 2009. Dimetrodon Is Not a Dinosaur: Using Tree Thinking to Understand the Ancient Relatives of Mammals and their Evolution. Evolution: Education & Outreach 2:257–271.
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