Friday, May 25, 2007
In a very bizarre news story, scientists have confirmed that a female hammerhead shark at the Henry Doorly Zoo in Nebraska has reproduced by parthenogenesis, meaning that is reproduced ASEXUALLY! Although this escapade began in 2001 with the seemingly virgin birth of a pup that was, unfortunately, immediately bitten to death by a stingray, it is only now that new DNA profiling techniques that have allowed scientists to say definitively that this was done without the assistance of a male. This was also anecdotally confirmed when all three female sharks were found without bite marks - a hallmark of shark sex.
Scientists are attributing this phenomenon to the extreme pressure of finding a mate among the sharks. It it seems that the population is so overfished that the female will often go so far as to leave out the role of the male. This occurrence is rare in vertebrates, but occurs regularly in some insects like bees and ants who use it to create more drones. That said, a case similar to this was reported Winter of 2006 when a Komodo dragon of Chester Zoo was found to also have had a virgin birth experience. In a poetic touch of nature, her eggs hatched very close to Christmas.
While this may seem like a very cool thing for perpetuating a species that is becoming increasingly endangered, Darwin and evolutionary biologists would says otherwise. By not reproducing with males, the independent females are reducing the genetic diversity of their offspring. This denies their offspring potential traits that may make them more fit to deal with changing environmental conditions. Zoos are now recommending that animals that have the potential to reproduce parthenogenically be kept in captivity with members of the opposite gender to ensure the opportunity for sexual interaction.
I think Stanford addressed this years ago by creating coed housing. Three cheers for biodiversity!
By the way, check out my Amazon Review of God Delusion.
Thursday, May 24, 2007
You can find my review of Sam Harris' Letter to a Christian Nation here.
I was actually kind of disappointed by this book, and I'm gonna try and read something from the other side now. I consider myself agnostic and have always been pretty critical of organized religion, but for some reason, Harris' book didn't really fuel those feelings in me; it kind of pushed me in the other direction. I think it will be easier to think about once I hear from the opposing side. The most important thing that it made me realize is just how pointless this whole battle is. He says that interfaith approaches don't work because by the very principles of religion a devout believer of one religion is going to think that every other religion is incorrect. But this is the exact same way the war between atheists and religious right is, and the battle between evolution and creationism. For one to be right, the other must be wrong. There's no middle ground, so I think the real issue should be, how can we even begin to talk about this in a civilized way? I'm starting to wonder if we can at all. What do you think?
Tuesday, May 22, 2007
In Darwin's last chapter, "Recapitulation and Conclusion" he briefly explains what he discusses in each of his preceding chapters. He uses strong statements like "the truth of these propositions cannot I think be disputed" (435) to affirm his general theory of natural selection. However, at the same time, when he addresses the details he acknowledges the imperfection and conjecture involved in forming some of his conclusions.
After he goes through his main arguments, he counters those of his opponents. He anticipates the controversy to come those upholding the creationist view. I thought his comment about the urge to "hide our ignorance under such expressions as 'the plan of creation'" (453) shows gumption on Darwin's part, especially in light of his reluctance to involve himself in any controversy. However, on the other hand, even though Darwin sees that his ideas will be difficult to accept, he sees hope in the "young and rising naturalists" (453). His faith in the next generation of minds reminds me of Thomas S. Kuhn's book, "The Structure of Scientific Revolutions". In his book, Kuhn addresses a similar idea, that often a true shift in paradigm requires an entire generation, because of the deeply embedded ideas of scientists working within the frame of accepted laws.
In his concluding paragraphs, Darwin opens the door for future scientific inquiry. For example, he writes, "we are as yet very ignorant of the full extent of the various climatal and geographical changes" (437). He even assets that "we can dimly foresee that there will be a considerable revolution in natural history" (455). He then goes through the different fields of science for which he sees such a revolution, such as genealogy, embryology, geography, geology and psychology. In Darwin's "prophetic glance into futurity" he foretells correctly that his ideas will have massive repercussions. However, even he does not realize just how massive his influence will turn out to be for not only science, but also for thought in general.
Okay now, this is just a little ridiculous. I’m going to try to keep this summary short because I think everybody should go check out this article for themselves, but in less than a week, a 60,000 square foot museum dedicated to supporting literal Bible Creationism is set to open just outside of Cincinnati. The man in charge of this museum, Ken Ham, was a school teacher in Australia when he turned his beliefs to creationism and came to the US in 1987 to spread his ministry. Among other things, the publications made by his organization claim to “offer what they call scientific proof that the Earth is just 6,000 years old; the Grand Canyon was formed when a natural dam burst under the weight of Noah's floodwaters 4,300 years ago; and that all animals -- including the Tyrannosaurus rex -- were vegetarian before the fall of Adam and Eve brought sin into the world.”
Ham, who believes that evolution undermines the truth of the Bible and creates a “dangerous age of moral relativism which can be blamed for everything from racism to the Holocaust” likens himself to Martin Luther as a leader of a “new reformation.” And this isn’t some dinky operation that he’s talking about. The museum, which cost over $27,000,000 to make, is complete with animatronics models, a $500,000 planetarium, and a special effects theatre, and replicas of the Grand Canyon and scenes from the life of Jesus. It will be interesting to see how his exhibits attempt to back up the claims he makes openly in his ministry.
We have been discussing some interesting and colorful characters associated with Darwin and the evolution saga. (Darwin's virual facebook friends???) As a modern personage, Frank Sulloway certainly fits that bill. And speaking of bills, there are finch bills and Durham Bills (being the person who first turned me on to Sulloway.) Among other things, Sulloway was the 2006 Darwin Day Celebration speaker at Stanford. I have alluded to various aspects of Sulloway's work on a number of occasions. Given that we are discussing the evolution of Darwin, the lexographic analysis in "Darwin's Conversion" is particularly relevant.
Dr. Sulloway sent me this URL in a recent email so I guess it is vetted.
My article is about the Mars rover and new evidence that Mars might have had water on it. One of the wheels on the rover is broken and turns up a lot of dirt when the rover moves. Some of the churned up dirt has been found to be about 90% silica, a mineral that would have needed water to form. One theory for the silica formation is hot acid vapors from volcanoes interacting with water on the surface and another is hot springs.
Scientists are calling this one of the most exciting discoveries by the rovers, because well, water is "clement for organisms." I think this is pretty neat and just highlights all the possibilities and all that we don't know, especially about other planets. Also, I think it's pretty funny that this silica was discovered by a broken wheel.
Some interesting data:
the site was "altered 2,081 times by 68 editors between December 2001" and October 2005.
(As a side issue, my youngest son and I both agree that the graph reminds us of the southwest border of the U.S.)
Though Jefferson predates Darwin and the evolution debate by quite a few years, Jefferson is an incredibly important figure in today's debate about the role that religion should play in the U.S. government. We spend a lot of time discussing Darwin's intentions (and how his intentions matter) including his opinion of religion; the same scrutiny is placed on the Founding Fathers, especially by proponents of the American right, who argue that the religious views of the Founding Fathers imply that the U.S. was founded as a Christian nation.
This makes me angry. If anything, though the Founding Fathers do reference God, most of them seem more like agnostics or athiests. For example, in a letter Jefferson wrote to his nephew Peter Carr, he advises his young nephew to be critical of religion:
"... shake off all the fears & servile prejudices, under which weak minds are servilely crouched. Fix reason firmly in her seat, and call to her tribunal every fact, every opinion. Question with boldness even the existence of a God; because, if there be one, he must more approve of the homage of reason, than that of blindfolded fear."
Here's another interesting snippet from Article 11 of the 1796 Treaty of Peace and Friendship with Tripoli which was signed by President John Adams:
"As the government of the United States of America is not in any sense founded on the Christian Religion,-as it has in itself no character of enmity against the laws, religion or tranquility of Musselmen,-and as the said States never have entered into any war or act of hostility against any Mehomitan nation, it is declared by the parties that no pretext arising from religious opinions shall ever produce an interruption of the harmony existing between the two countries."
There you go. This is another example of how the intentions of important thinkers are really questioned and interpreted. Interpretations of intention are actually very important. For example, Justice Scalia of the U.S. Supreme Court is really into looking at what Alexander Hamilton thought about Federalism as a basis for making a Federalist interpretation of the constitution; Scalia discounts Thomas Jefferson's extreme disagreement with the Federalists because Jefferson was in France for some of the time during which the U.S. Constitution was drafted.
This week, my new and hot is an article from BBC News, and it's about the polar ocean CO² sink. I actually heard a grad student in one of my anthsci classes talking about this last week, but didn't think much of it until I was browsing news articles today.
The loss of efficiency of the carbon dioxide sinks was expected, but not for another 40 years or so. This is a serious problem because as the surface water becomes super-saturated with CO², it becomes more acidic, harming many ocean organisms, such as coral. You can find the full-text here.
These days it seems like Kansas is always in the news when it comes to [anti]evolution in the news, I find that really interesting. But in any case, the opponent supposedly dropped out of the race due to personal reasons and now a lot of educators are outraged and such. They really don't want this Willard guy to win and are hoping to be able to get on the ballot as write-in candidates during the July elections when they come around. The problem is, the NASBE doesn't have this provision for write-in candidates. So a lot of people think that Willard will basically be the president starting in 2009. Anyways, some people are unhappy about that.
http://www.nytimes.com/2007/05/22/science/22deep.html?_r=1&ref=science&oref=slogin "Mysteries to Behold in the Dark Down Deep: Seadevils and Species Unknown"
Everyone should check out these photos- the article is a review of a book that published all these amazing pictures of deep-sea creatures, organisms that could not previously be photographed (because of the difficulties of creating a camera that could withstand such pressure) and that disintegrated into shapeless blobs when exposed to air and released from their normal water pressure. They're just bizarre.
The photos reminded me of the conclusion of The Origin of Species- Darwin spends a fair amount of time recapitulating the arguments against evolution by natural selection, and he refutes many of them by reminding his readers of how little we know. We can't tell the difference between varieties and species irrefutably, we can't comprehend the amount of time evolution would take (or the age of the Earth physicists told Darwin), we don't have all the intermediate species available in the fossil record, and we can't know how many countless species have gone extinct without a record. Darwin draws his conclusions about evolution based on what he was able to observe, but he was very conscious of the fact that there was much more he never could observe or understand. That he presented a theory, supported by an enormous amount of facts, but refused to call it an absolute truth, speaks to his humility as a proper scientist. Because of his open-mindedness, Darwin's theory still fits with the new species being discovered, species built using familiar plans, but with new adaptations for their extreme environment. As he points out in the Origin, if every species were created individually, there would be little reason why in this new (deep-sea) environment creatures would resemble species nearby, but in very different environments, instead of being a truly distinct act of creation.
Monday, May 21, 2007
For me, these statistics are both staggering and disconcerting. It's incredible that one individual could have such an immense influence on the genetic makeup of such a large portion of the modern world. It's also a little frightening to think that the individuals who have had the greatest influence on the global gene pool were not nice, meek individuals, but tyrants, mass rapists, and conquerors, who forcefully spread their seed to possibly tens of thousands of offspring, which then multiplied as the generations passed. Nevertheless, the fact that you don't see most of us trying to take over the world despite this selection for aggressive traits suggests that there must be a strong counteracting selection for altruistic traits as well.
Read the article here.
To start out though, I wanted to ask him about some of the issues relating to the Galapagos that we have been talking about. In one of my other posts I wrote about articles that I had read about the destruction of the Galapagos and tourism. Klaus wrote a really interesting response to my question that reaffirmed that tourism is not as big of a problem as more domestic issues. He wrote:
“Lately there has been a lot of media exposure about Galápagos, partly because of the President’s declaration of Galápagos under emergency. Right away this triggered the next response with all fingers pointing at the excessive numbers of tourists as the main problem and everyone imagined iguanas and sea lions trampled by hordes of visitors. A few weeks ago, a head of UNESCO made a remark about too many visitors in Galápagos. I see this as too much excitement over the wrong evil. Tourism has increased, true. But it is far from being a hazard. Last year we had 148 000 visitors. I have to say that every time I fly to Galápagos (five times in the last two months) I count as another visitor, so the actual number of tourist is much smaller (98000 foreign visitors, in fact, and a number of Ecuadorian too). But high as these figures may seem, keep in mind, that in a single soccer stadium, in Brasil, there is room for 170 000 seated spectators, for one and a half hours of 22 men chasing a ball. Galápagos is in season all of the 365 days of the year. The problem is not there (if you’d see the same trails as a decade ago, you wouldn’t notice the slightest decline of boobies, iguanas, albatrosses or else, right on the trails, nor would you notice a tiny piece of garbage),but in the 3% of Galápagos that is not protected. The inhabited side. And there the problems are many. Starting with a great population growth (5 to 6% yearly) to the problems attached to any human settlement. But Galápagos got to be a true disaster as far as institutions. And here is where the decree of emergency comes in. Consejo Provincial, Municipios, Instituto Nacional Galápagos, Servicio Parque Nacional Galápagos, Direccion General de Marina Mercante, Armada del Ecuador, Gobernación Galápagos, etc are only some of the maze of institutions involved in managing Galápagos. A state of emergency allows the Government to by pass a lot of endless red tape and clean up the institutional mess. Conservation issues like quarantine and eradication program of introduced species will be addressed promptly and efficiently. The wildlife beyond these 3% is doing well as ever!”
I also asked him about Lonesome George since we had the opportunity to see him when I was in the Galapagos. Klaus disclosed some really cool news not well known to the public! There actually may be another male in Prague that could potentially save the subspecies! He also brought up a good point. The species is technically already extinct because there is no female. I thought that this portion of his response was pretty funny as well, so I included it. He wrote:
“Lonesome George? Well he is fine, in his usual celibacy. DNA has determined that indeed he is the last member of his subspecies (a status under debate
is the thin line that separates a species from a subspecies is not only thin these days but extremely blurry and far from being consensual) in Puerto Ayora at the Charles Darwin Research Station. However, there seems to be at least one confirmed back-up for ol´George. Another male tortoise of the abigdoni ssp lives a happy tortoise life in Europe (Prague, to be precise). Because Lonesome George is without a trace of doubt, the world´s most famous tortoise (I dare to go further and call him the world most famous reptile, other than Barney), and as such, we may not stir up too much attention to a brother elsewhere. Terribly important for making every attempt to save the subspecies, no doubt, but perhaps not the best marketing move if announced too loudly. This is my personal view only! In a scientist level, contacts are made to deal with this close encounter with extinction (technically, George is extinct, as a single male does not qualify as a species- both genders are needed!).”
As you can see Klaus is truly passionate about what he does and he would love to address any questions about the Galapagos or anything else that comes to mind! Let me know!
This picture is just a random picture I found on the web. I thought it was cool :)
The article is entitled "Climate Change Also Drives Evolution," and it talks about how animals are having to adapt more rapidly because of the effects on climate & environment due to human causes. The article brings up 3 specific examples. The first is that codfish are not reaching sexual maturity earlier than before due to human fishing practices. The main point is that if you're a codfish and you wait until you get really big to procreate, then chances are, it'll be too late...you'll be on someone's dinner plate first. Thus, now, codfish reach sexual maturity at around 6 years, instead of 10 years. This change took about 40 years to occur in codfish populations, but a similar phenomenon can be observed in guppy populations within only 5 years. Research has shown that "if the oldest guppies are retired from a population, their sexual places are occupied by younger exemplars."
Also, different species of birds are now observed in new, previously thought less-than-optimal environments. The white-tailed eagle provides one example. About 15 years ago, it was believed that this bird could only live in the large forests of Central Europe. However, recently, the white-tailed eagle has been found in Northern Germany, Poland, and Scandanavia.
Thus, the world's biodiversity is adapting to an environment influenced by human factors. In some cases the result is depressing, with ~150 species dying off each day, but in other cases, the result is more hopeful, particularly when species are able to adapt more rapidly. However, is rapid adaptation beneficial to the species in the long run?
In an exciting twist new twist for human development in the Americas, scientists are unveiling evidence this week that a blast from a comet or asteroid caused cooling in North America about 13,000 years ago. They have gathered geological evidence from 20 sites in North America that contain glass, carbon, iridium and nanodiamonds that could not possibly have come from the earth. All this points to the theory that a 5km object impacted the earth or exploded in the sky causing massive wildfires followed by a 1,000 year cooling period known as the Younger Dryas.
What's really cool about this, though, is the implications it has for explaining extinct species. It seems that the date corresponds perfectly with the extinction of most large mammals in North America at the end of the last Ice Age. Mastodons, giant ground sloths, short-faced bears, sabre-toothed cats, and North American camels could all trace their extinction back to this one event. Since I'm reading about Darwin's explanations for gaps in the fossil record for transitional state animals and such, it is interesting to read about theories that point out that fossil records may be spotty because of these sudden catastrophic events.
While interesting, this theory does have some caveats in it as well as conflicts with other theories on the topic. While this theory states that human populations were largely decimated, much evidence and scholarships has pointed out that early Meso-Americans were moving and growing at this period of time, not declining. Also, some would argue that if this explosion occurred, then where are the crater remains. This of course is explained by the fact that the Laurentide Ice Sheet that covered much of North America masked the impact. Still, this is obviously a theory that still needs some tweaking. Perhaps future research will shed some light on where all the mastodons went.
Click here for the story from BBC
Sunday, May 20, 2007
Today, I found an article about a new Young Earth Creationist Museum that has been built near Cincinnati. The museum features such exhibits as a girl feeding a squirrel while baby T-rexes play nearby and a half-million dollar planetarium aiming to show the glory of the heavens. The museum teaches that the Grand Canyon was a result of a natural dam breaking during the great Biblical flood and many more "facts" that attempt to disprove the established science of evolution.
What I found most appalling was the following exhibit bordering on racism. From the article: "An animatronic display sums up their argument: two paleontologists are examining the same dinosaur fossil. The evolutionist - an Asian man - comes to one conclusion while the creationist - a white man who resembles Ham - comes to another."
Did I say bordering?
The article can be found here .
This article describes how researchers at the University of Illinois have created a phylogenetic tree (family tree) that tracks the evolution of proteins. They formed the tree on the assumption that protein folds (areas of activity) that were used by the most species were the oldest. They looked at 776 protein folds used by 200 different species of bacteria, archaea, protists, animals, plants, and fungi. 16 of the folds found were universal across all species, and nine of these evolved around the time of the earliest divergences of species. The researchers wrote that “These nine ancient folds represent architectures of fundamental importance undisputedly encoded in a genetic core that can be traced back to the universal ancestor of the three super kingdoms of life.”
What makes these results exciting is that the nine oldest folds are involved in RNA metabolism. The current hypothesis about the origins of life states that life was originally RNA based, and that self-splicing RNA both carried genetic material (from which it could make proteins) and had metabolic function (that enabled it to make proteins-important because DNA requires the use of proteins to transcribe genes). If the oldest proteins do contain RNA activity, then the earliest life most likely was RNA based.
May 19, 2007 New York Times
In July, the National Association of State Boards of Education (NASBE) will be electing new officers. NASBE is a nonprofit organization of state board schools with the objective of improving leadership in educational policymaking. The only candidate for president in this election is Kansas Republican, Kenneth Willard. In 2005, Willard voted for changing Kansas' science curriculum to permit intelligent design to be taught in schools. There was another candidate for the presidential NASBE position, but he had dropped out due to personal reasons.
Scientists involved in this educational policy debate hope that states will write in other nominees instead of accepting Willard by default. Some are concerned that if Willard is elected, then the issue of teaching evolution or intelligent design will be taken to the national level, rather than be left up to states to decide. Others feel that science education is at a crucial period so "any situation that provides an opportunity for the opponents of science education to advance their agenda is a matter of concern."
Willard said that while he does believe students should be taught about alternatives to evolution, such as intelligent design, that the purpose of NASBE is not to set school curriculum but to deal with other issues such as promoting academic success for disadvantaged students. He also commented, "Some people are mindless about their attacks on anyone questioning anything Darwin might have said."
While I agree that it is concerning that an intelligent design proponent may hold this presidential office, should we really be worried? How much will Willard's opinions on evolution affect NASBE if this organization does not make decisions about what is actually taught in school? It seems that Willard's conservative background would affect the organization more than his specific thoughts on evolution. I also thought that the quote I included from him was an interesting role reversal. I normally don't think of scientists as mindless. Instead, I can imagine an evolution advocate making this comment about a creationist.