Science & Nature Archive

Thursday, August 9, 2012

The Roots of Morality

I don't often have posts that are little more than embedded YouTube videos, but this one was too good to pass up. A few months ago, Frans de Waal gave a TED presentation: Moral behavior in animals. I'd highly suggest following that link to watch his full presentation, but one of the videos he showed has been pulled out into it's own YouTube video. The video is of an experiment with capuchin monkeys. These monkeys had been trained to return a rock that a researcher gave them in exchange for a treat. It's important to note that capuchins like certain treats more than others. A piece of cucumber is decent, but they really like grapes. I suppose it would be like the difference in getting a piece of hard candy from your grandmother vs. crème brûlée in a 5 star restaurant (or substitue according to your tastes). In this particular experiment, there were two monkeys involved, each in a separate cage, but adjacent to each other so that they could see each other. The first monkey returned the rock to the researcher, and received a cucumber in return as a treat. The second monkey returned the rock to the researcher, but received a grape in return, which the first monkey clearly saw. Next, the researcher went back to the first monkey, and again gave it a cucumber in return for the rock. Watch the video below to see the monkey's reaction.

This may not be a full sense of morality as developed in humans, but it's certainly a part of it - recognizing an unfair situation. It amazes me just how human like the monkey's reaction is. It reminds me of how a young child with poor impulse control might react.

Now, I know there are dangers in over anthropomorphizing, but really, when we're so closely related to an animal, doesn't it make more sense to think that their thought processes are at least similar to ours, rather than thinking that humans evolved all these brand new and novel characteristics in an evolutionary blink of an eye?

I'll note that I first saw this on Jerry Coyne's Why Evolution Is True. Follow that link to read some good discussion of the video (along with some rather close minded remarks by one particular commenter).

Tuesday, July 17, 2012

Why Study the Higgs Boson?

With the recent news over the probable discovery of the Higgs Boson, I've seen an old question come up again - What's the point of doing this type of research?

I've covered this before on the blog in the essay, Knowledge for Knowledge's Sake. That essay was in reference to dark matter, but it's largely applicable to the Higgs Boson, so I'm not going to repeat myself here. However, I've seen a few good takes from others on this question.

First is an article in the New York Times by Steven Weinberg, Why the Higgs Boson Matters. Jumping to the end, here was his conclusion:

On a longer time scale, the advance of technology will reflect the coherent picture of nature we are now assembling. At the end of the 19th century physicists in England were exploring the properties of electric currents passing through a near vacuum. Although this was pure science, it led to our knowledge of the electron, without which a large part of today's technology would be impossible. If these physicists had limited themselves to work of obvious practical importance, they would have been studying the behavior of steam boilers.

Next is an article by Jerry Coyne, which used Weinberg's article as a starting point, Steven Weinberg on the Higgs boson, and a few words on the value of pure science. Here's an excerpt of what he had to say:

But I wish we could convince the public that there are simple payoffs in understanding. Humans are curious animals: we want to know where we came from, and where the universe came from, and what we and the universe are made of. That is worth something in itself. Even if evolutionary biology had no practical benefits (and yes, there are some, but the vast amount of money given us by taxpayers to study evolution is to promote pure understanding), it would be worth spending money on, just as we subsidize the arts.

And finally, a recent comic on Saturday Morning Breakfast Cereal made the point quite humorously. Here's the first panel from that comic. Click on it to read the whole thing:

SMBC #2674

Saturday, July 7, 2012

Arguing on a Website - Explaining Evolution

Evolutionary TreeI didn't write much on the blog this week because I spent a few lunch breaks getting caught up in a discussion in the comments section of an article in the local paper. So, I'll do what I often do in these situations, and copy my comments here. It's a bit repetitious of other things I've written before, but due too the nature of comments, a bit briefer.

You should read the Letter to the Editor that kicked off the conversation first. Be warned that much of the discussion in the comments section degraded into name calling, triggered by the second letter at that link.

Here's my first comment.

Although I agree with much of the sentiment of Jim Edwards, I did see a few places where what he wrote is in need of correction, or where I might add a litte more information.

"First of all man did not evolve from apes."

Granted, this is a semantic issue, but it's one of my pet peeves. Humans did not evolve from any of the other extant apes, true. We didn't evolve from chimps or bonobos (they didn't evolve from us, either). We all three species share a common ancestor. Further back still, we share a common ancestor with gorillas, and even further back with orangutans. But if you were to get in a time machine and travel back to any of those common ancestors, whatever species they might be, they would still be referred to as apes. It would be like arguing that crows didn't evolve from birds, but only share a common ancestor with birds.

Regarding the time of the split, the current best estimate is around 6 million years between us and chimps & bonobos. The other apes split off from our lineage earlier than that. You have to go back around 20 million years for the split between old world monkeys and us apes, and back around 30 million years for the split with new world monkeys.

If you're really interested in the family tree, just google "primate phylogeny".

Regarding 'missing links', I'm not sure what people expect them to look like, but there are plenty of transitional fossils that have been found. To give just two examples, tiktaalik roseae is a great example of the transition from fish to tetrapods, and ambulocetus is a great example of the transition from terrestrial mammal to whale. But keep in mind that these examples don't rest solely on their own. You have to look at them in context of other fossils. For example, animals like Eustheopteron and Panderichthys are similar to Tiktaalik, but more fish like, while animals like Acanthostega and Ichtyostega are also similar, but more tetrapod like. On the human side, just google "talk origins hominid skulls", and you'll find a page showing skulls grading gradually from earlier hominid ancestors into us modern humans.

And my second:

tdgriffin wrote:

"I have no doubt that the DNA of apes and humans are similar. I wouldn't be surprised if doves and pigeons have similar DNA. They resemble each other. It doesn't prove they came from the same ancestor."

Why would our DNA be so very similar to that of a chimp's if not for common ancestry? Let me use an example. Most animals can make their own vitamin C. They don't need to eat foods high in the vitamin because their bodies simply synthesize it from the other molecules of the food they eat. Scientists have found the gene responsible for this, the L-gulano-γ-lactone oxidase gene. They've found a broken copy of this gene in humans. So the first question is, why would we have a broken copy of a gene, unless we inherited it from an ancestor with a functioning copy? Now, I know some creationists might say that maybe Adam and Eve did have functioning copies of this gene, and mutation crippled it. But guess what, scientists have also found this gene in chimps, macaques, and other primates, and it's broken in the same location as the human copy. So now you have to accept that this gene either just happened to mutate in the same location in all of these different animals, or that a creator intentionally put the same broken, non-functioning gene in all these animals, when it just makes so much more sense to assume that it mutated in a common ancestor of all these animals, which passed it on to all of its descendants.

(As to why a broken gene could have persisted in successful animals, if you're eating a diet rich in fruits and vegetables, it really won't hurt you if you can't make Vitamin C, so there's no selection pressure for those individuals with a working copy vs those with a broken copy.)

And L-gulano-γ-lactone oxidase isn't the only example. We share other pseudogenes with the great apes, and similarities in 'junk' DNA also match the pattern predicted by common ancestry.

And then my third and final comment:

in response to tdgriffin:
So, I take it you disagree with me? Oh well. But I still wonder why we, in our never ending quest for the perfect species, would hang onto a broken copy of an unnecessary gene over millions of years, since we and the apes decided to go our separate ways. When I break a cd, I chunk that bugger.

Another thing I wonder about, when I hear it mentioned: Just how many generations would it take for a black family living in New York to become white, or a white family living in South Africa to become black?

Natural selection only acts on beneficial or harmful traits. Beneficial traits allow an organism to have more offspring, so that trait becomes more common in a population. Harmful traits cause an organism to have less offspring, so that trait becomes less common in the population. Neutral traits aren't acted on by natural selection, and can persist (although, in the long run, neutral traits tend to deteriorate or drift just because there's no pressure from natural selection to maintain them). Also keep in mind, that there's no mechanism in our cells to do what you propose - cut out bad sections of DNA. Our cells just copy the DNA, making a few mistakes here and there in mutations. And of course, there's no conscious intent. You can't will your cells to cut out your broken L-gulano-γ-lactone oxidase gene in the sperm or eggs that you'll provide to your children.

So, some of our distant ancestors lived in an environment where they ate lots of fruit and vegetables, and got plenty of Vitamin C from their diet. When some mutation occurred that crippled Vitamin C synthesis, it didn't help or hurt that individual. Even if a mechanism existed to do it, cutting out the broken gene wouldn't have been noticeably beneficial. It was a neutral mutation. So, it didn't hurt that individual's chances of having offspring, and the broken gene began to spread.

But now there is an interesting question - if the broken gene wasn't beneficial, how did it become so widespread as to become fixed in the entire population? Here's where it's good to remember that populations are composed of individuals, and that sometimes a little bit of chance comes into play. From time to time, there will be population bottlenecks. This may be due to hard times that kill off most of a population, or from a small group becoming isolated and then developing into a new species. So when you get down to those small population sizes, chance plays a big role in which versions of genes are present and, and consequently which will persist in that population. (You can read more about this on Wikipedia under 'Founder Effect': http://en.wikipedia.org/wiki/Founder_Effect

As to the question of skin color, I honestly don't know, but I suspect that in modern times, it might not happen at all. Remember that in evolutionary terms, 'fitness' merely means successfully leaving offspring. And for natural selection to act on a trait, it has to result in individuals having either more or less children than other individuals with different traits. In modern day New York City or modern day South Africa, where much of people's lives are spent indoors, and where dietary supplements are readily available for those with Vitamin D deficiencies, I doubt there's any strong selection pressure on skin pigment.

Thursday, June 7, 2012

Venus Transit

Other people got much better photos of the Venus transit than I did (see Bad Astronomy or Why Evolution is True for a few), but this is my blog, so I'm going to post mine. I used my daughter's Astroscan telescope, with a sun viewing screen to project the image onto. So, here's the transit, taken with my iPhone. It's a little skewed because the camera was off to the side.

Venus Transit

And just to show the telescope setup, here are a couple photos of that.

Venus Transit

Venus Transit

I also installed a Barlow lens to get even more magnification - the sun wouldn't even fit on the screen. At that size, there was a very noticeable shimmering around the edges of Venus (I think due to a phenomenon known as astronomical seeing). I tried to take some video of that, but none of the videos turned out well at all.

Wednesday, May 23, 2012

Theistic Evolution vs. Intelligent Design

Theistic EvolutionI must be getting old - I'm becoming forgetful. Jerry Coyne recently wrote a post titled Does theistic evolution differ from Intelligent Design?. I left a comment on his site, and had already started to write a blog entry expanding on that, when I came across an old entry of mine that said almost exactly what I was planning to write, Difference Between ID Proponents and Theistic Evolutionists. Oh well, since I already have some of this written, I might as well go ahead and post it so as not to waste the effort.

Coyne stated his position right in the introductory paragraph.

My answer is that these two brands of bad science elide seamlessly into one another, with no sharp line to demarcate them. Nevertheless, I don't call people like Francis Collins advocates of ID simply because that term conflates them with the hard-core, get-in-your-school adherents of ID who populate the Discovery Institute. But let us remember that this is a quantitative and not a qualitative difference.

He went on to write in his penultimate paragraph:

If you think that an intelligent god intervened in the process of evolution, especially to ensure the appearance of human beings made in that god's image, then you're advocating intelligent design. If you accept even a little bit of divine tinkering in the evolutionary process, you're not standing on some inclusive middle ground--you are, as P.Z. Myers said, halfway to crazy town.

I understand that both concepts are related, and maybe there is a grey area in between them. But I think there is an important difference between the two positions. To a proponent of theistic evolution (TE), if you take away God, evolution continues to work, you just may not end up with humans. To a proponent of Intelligent Design (ID), if you take away God, evolution is vastly different, without any complex structures. In other words, a TEist accepts all the evidence for evolution, but adds in an extra mechanism on top of it to accommodate their religious belief. An IDist rejects all the evidence for evolution, and invents a mechanism to replace it.

Part of the problem is that ID is so poorly defined. But even someone like Michael Behe, who accepts a bit more of the evidence for evolution, still accepts irreducible complexity, and believes that some features of organisms just couldn't have come about without divine intervention (or alien intervention, if the less honest press releases from the Discovery Institute are to be believed). And if you look at something like the ID textbook, Of Pandas and People, it reads like straight up creationism. Here's a passage from page 22 of that book that I've quoted twice before on this blog.

Instead, fossil types are fully formed and functional when they first appear in the fossil record. For example, we don't find creatures that are partly fish and partly something else, leading gradually, in the dozens of characteristics which they exhibit, to today's fish. Instead, fish have all the characteristics of today's fish from the earliest known fish fossils, reptiles in the record have all the characteristics of present-day reptiles, and so on.

And here's another one from page 25.

There is, however, another possibility science leaves open to us, one based on sound inferences from the experience of our senses. It is the possibility that an intelligent cause made fully-formed and functional creatures, which later left their traces in the rocks.

And as I pointed out in that previous post of mine, what else can you expect of a theist? They see God's intervention in everything, from the weather to diseases to coin tosses. Why would they leave evolution out?

I also disagree with Coyne implying that because the two positions "elide seamlessly into one another, with no sharp line to demarcate them", that they shouldn't be considered as different. The same argument can be made for many things, from colors, to night and day. I'm especially surprised at an evolutionary biologist using this argument*. If you could get in a time machine and see every individual in the lineage from one of our ancestors from 6 million years ago to today, you'd never be able to pick out just exactly when one species transitioned into another. But I don't think anybody would try to argue with the fact that we're a different species than that 6 million year old primate.

So, while TE and ID may be related in that they both see the hand of God influencing the history of life on the planet, there is enough of a distinction between the two positions to merit separate labels.


*Don't take this as an attack on Coyne. I have great respect for the man, read his blog website almost daily, and think his book, Why Evolution Is True, is possibly the best introduction to evolution for people who don't know much about it.

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