On BioScience and Life and Such

Posts Tagged ‘darwinian evolution’

They say men haven’t evolved towards domestic use

In Uncategorized on September 10, 2009 at 2:11 pm

post to news.thinkgene.com

Male symbol. Created by Gustavb.

Image via Wikipedia

First off, I have to admit that my scientific knowledge is a bit sketchy on this one. Nevertheless – my impression is that there is a (scientific ?) consensus out there saying the following:

The nature of men is that of the restless promiscuous hunter. Evolution has provided pressure towards maximizing the spread of male genes through procreating with as many women as possible. This way the number of offspring one man can obtain is maximized. Apparently observations supporting this view are the vast amount of sperm cells produced in the male reproductive organs and the continuous (not cyclic) nature of this sperm-production. The logic is, I think, that the production of all these sperm cells would be futile if destined for only one woman with a cyclic reproduction cycle. So far so good.

Consequently, the masculine “nature” is continuously compromised in our modern monogamous lifestyle. Male infidelity is often excused using the arguments above. The same arguments also makes domestic life and caring for the family into a compromise with “natural” masculinity.

Still good ?

Even if making as many offspring as possible seems like a good strategy to pass on (male) genetic material, isn’t it possible that another strategy would work just as well.

You could argue that continuous sperm production is present to counter a single woman’s unpredictable cycle, – or compensate for miscarriages, – or compensate for children born by this woman dying young (not so rare in those older days). This make-one-woman-pregnant-many-times strategy could potentially lead to as many offspring, themselves reaching reproductive age, as the multiple partner strategy.

If you buy into that last argument, there is no reason why the selective pressure on men has been towards domestication and taking maximal care of his one-woman family. And, against inclination towards infidelity.

I’m so sorry for ruining our excuses here my fellow men, but the whole man-as-a-hunter-excuse has been bugging me for a long time. I find it hard to understand why such an idea has been elevated to universal truth. I believe a need for behavioral excuses has overridden scientific rigor on this one. Anyone who can convince me otherwise is more than welcome.

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Are you Suffering under the Creationist Terror Regime

In Uncategorized on October 8, 2008 at 9:23 pm

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Then free yourself……now !!

While reading “Postmodern evolution?” (a Nature News feature by John Whitfield) I found myself ripped out of the general feeling of bliss (caused by the fact that evo-devo is finally gaining some momentum). Because, first I read this:

Günter Wagner, an evolutionary theorist at Yale University in New Haven, Connecticut, puts up a slide bearing the words ‘Postmodern Synthesis’. Pigliucci is moved to make an editorial suggestion from the floor: “I’d really rather we didn’t use that term.” Wagner says the slide was intended to be tongue-in-cheek, but Pigliucci is worried about the impression the word creates: “If there’s one thing we don’t want, it’s for people to get the idea that there’s a bunch of evolutionary theories out there, and that they’re all equal.”

So, …. are we all forced into silence by the creationists ? The advice is not to use a term because it illuminates that there are new ways of thinking about an existing (and accepted) theory. We cannot speak in fear of being misinterpreted ? Such a coward attitude !

And then to make things worse, towards the end I read this:

…the dominant political concern was a fear of attack from fundamentalists. As Gould discovered, creationists seize on any hint of splits in evolutionary theory or dissatisfaction with Darwinism. In the past couple of decades, everyone has become keenly aware of this, regardless of their satisfaction or otherwise with the modern synthesis. “You always feel like you’re trying to cover your rear,” says Love. “If you criticize, it’s like handing ammunition to these folks.

Well, discussing in this cover-up manner will in my opinion, provide even stronger ammunition. Science is not about keeping your silence, quite the contrary.

Sometimes accusations of damaging the Darwinistic cause are used by scientists towards other scientist, – an indication of a societal reign of terror. To illustrate, here’s a comment to Oliwia Judsons blog post on Hopeful Monsters:

A “jumpy sort of evolutionary process” explains the complex organism’s sudden appearance, because there isn’t fossil evidence? Be careful or you’ll soon be agreeing with the Intelligent Design folk that there is such a thing as irreducible complexity. And “so far the data are suggestive rather than definitive”? Well, that opens a whole another box of problems, doesn’t it, Ms. Scientist Judson? Speculative articles such as these masquerade as science and do great harm to the whole field.— Posted by Charles M

Many are, of course aware of the situation, but nevertheless ends up bowing in fear of creationist attack (again from the Nature News feature):

” So don’t criticize in a grandstanding way, says Coyne: “People shouldn’t suppress their differences to placate creationists, but to suggest that neo-Darwinism has reached some kind of crisis point plays into creationists’ hands,” he says.

The glue holding a regime of terror together, are terrorized people. But, why be afraid, – facts are on our side. We are free to safely discuss the implications of these facts. There is no danger in this.

So please, please, stop holding your arguments back. It does not serve the cause of solidifying evolution as a fundamental force in biology. Speaking clearly on all scientific views of evolution theory on the other hand will, and holding back only makes things worse.

Quote of the month July 08

In Uncategorized on July 7, 2008 at 11:31 am

Professor Lenski, at the very end of the Lenski Dialog:

I find it baffling, however, that someone can worship God as the all-mighty Creator while, at the same time, denying even the possibility (not to mention the overwhelming evidence) that God’s Creation involved evolution. It is as though a person thinks that God must have the same limitations when it comes to creation as a person who is unable to understand, or even attempt to understand, the world in which we live. Isn’t that view insulting to God?

Baffling indeed.

P.S. Take care not to confuse Conservapedia (where the link takes you) with Wikipedia or other objective and neutral sites, – Conservapedia is a conservative christian site.

On ScienceBlogs 27/-1-08: Quick-Change Evolution

In Uncategorized on January 27, 2008 at 9:46 pm

I have so much to learn, and I’m looking so much forward to learning it. This time around it’s in evolution theory, and I’m going to make some bold statements while learning.

Some recent posts here on SciPhu has been on Hsp90 and rapid morphologic evolution. On ScienceBlogs the topic of the day is Quick-Change Evolution. The background is a blogpost by Olivia Judson stating the return of the hopeful monster. The hopeful monster theory says that extensive morphologic changes in one individual offspring (a monster – an individual organism looking radically different from the rest of its species), sometimes creates beneficial features enabling the monster to create further offspring with similar features. In this way one can achieve rapid evolution (as short as one generation) into the beginning of a new species. The theory is a controversial one and is also called punctuated equilibrium. I however, am apparently at odds with most science bloggers and evolutionary biologists, since the hopeful monster theory sounds plausible to me. How is this linked to Hsp90 you may wonder. Well…

Knocking down Hsp90 creates rapid morphological changes from one generation to the next (for details see references in my previous posts Evolution too fast for our genes to follow, On Hsp90 and morphological evolution and The rate of evolution/mutation/adaptation and future posts to come). Hsp90 does so by masking mutations under normal conditions and then revealing them under stressful conditions. Just to repeat myself, – this concept suddenly made evolution comprehensible to me, and I do not understand why other scientists haven’t embraced the masking concept as a revolutionary concept, expanding darwinian evolution theory.

Now it’s dawning on me why…….Such masking of mutations to produce a pool of potentially crucial mutations gives support to the hopeful monster theory.

One of the main criticisms of this theory, as far as I can understand, is the improbability of a single mutation to give rise to radical morphological changes, and further that this change, if it happens, is most likely deleterious, and if it against all odds is beneficial, its even more improbable that this individual is able to produce offspring with the same trait(s). But…..

Extensive morphological change has been shown to happen due to single mutations, and…

With Hsp90 as a player in the game, it need not be a single mutation, but rather a pool of mutations already present and waiting to be exposed under stress. That increases the chances of achieving multiple changes in multiple individuals. Consequently the chance(s) of producing one or more beneficial trait(s) is(are) increased.

In addition, if such stress appears and mutations are revealed, then many individual offspring will have extensive changes, and the chances for two such individuals to mate increase dramatically.

Thus, I cannot see why a combination of the hopeful monster theory and the actions of Hsp90 (and possibly other mutation masking proteins) under stressful conditions, is a perfectly credible extension to darwinian evolution. An extension that can explain some of the rapid changes that has occured during evolution of species.

The rate of evolution/mutation/adaptation

In Uncategorized on January 3, 2008 at 1:48 pm

I came across this blogpost from evolgen which is a part of a discussion with John Hawks on increased rate of evolution. It seems to me that the term “neutral mutation” is central in this discussion. However, looking at the effect of Hsp90 as described in my previous posts (and future posts to come), – is it possible that some of these “neutral” mutations aren’t neutral at all, but rather deleterious or beneficial mutations masked by a heat shock protein ?

I am in over my head when it comes to in-depth analysis of population genetics data, but still, to me, – the action of mutation masking Hsp’s (if this is truly a valid evolutionary phenomenon) may seem to bridge these two opponents as well as solving a lot of other controversies surrounding the rate of molecular evolution vs. phenotypic/morphological evolution.

Evolution too fast for our genes to follow

In Uncategorized on December 20, 2007 at 1:41 pm

In the near future, the upcoming posts will center on Heat shock protein 90 (Hsp90) and how the function of this particular protein can explain rapid morphological evolution, or rapidly evolving phenotypic variation if you will. The topic and papers on it, are in my opinion hugely underrated. To me, until these papers came out, the extremely rapid (in a cosmic timescale) change in physical appearance that is seen in the evolution of species, was the major (only ?) valid argument contradicting Darwinian evolution through random mutations and genetic drift. This because genetic drift through random or even guided mutations, is just too slow to explain the evolution of such a vast spectrum of species as the one present on earth, in such a (relatively speaking) short time. The concept of masking mutations through the action of Hsp90 was an eye-opener and presented me with an extension to genetic evolution that explained rapid phenotypic change. Thank god(!) for this possible counter argument towards the missing link babble presented by creationists and their like. And it is surprising that these papers haven’t been used more in discussions concerning evolution. More details on Hsp90 to follow, but the fundamental paper is (not open access unfortunately): Hsp90 as a capacitor for morphological evolution Nature 396, 336 – 342 (26 Nov 1998).