Summer Assignment 7.22

Just one story this week; a longer piece on why we have blood types by one of my favorite science writers Carl Zimmer. You probably (hopefully) remember something about blood types from previous classes, and may even remember how to do the genetic crosses to figure them out. But have we ever thought about why we have different blood types? I know I never had until I read this article. Lots of interesting stuff in here, and overall it highlights a very important fact of evolution: If it exists, it most likely has an adaptive advantage.

Slime molds and evolution

Interesting story by Carl Zimmer in the New York Times about slime molds. They really are fascinating organisms, and can tell us a lot about evolution. And I love the practical uses people are finding for them, like designing highways, or planning how to reroute highways in case of a nuclear meltdown.

Summer Assignment: 8.16

A couple articles about interesting evolutionary adaptations in animals this week. The first one is about Müllerian mimicry in a butterfly species. This type of mimicry involves one species mimicking a bad-tasting species. This particular butterfly species can mimic a wide range of species, and the genes for these differences were all mapped to one chromosomal region, or "super gene."

The second article is about behavior in a spider species called whip spiders, or whip scorpions. If you don't like spiders, I suggest only looking at the first article. These spiders have evolved a vibration-based communication system which they use to peacefully resolve male-male conflicts. Researchers wonder if this system is used by other arthropods, since the detection hairs are conserved across the group.

Links:

These Butterflies are "The Transformers of the Insect World" — And the Answer to an Evolutionary Mystery

The Threatening Vibes of Whip Spiders

Summer Assignment: 8.9

Scientists Create Spermless Males to Fight the Spread of Malaria

Interesting new research in malaria prevention, which has shifted more towards mosquito control due to the emergence of resistant strains of the parasite. Scientists had thought for a while that controlling the reproduction of the mosquito would be an effective means of fighting the disease, but there was no good way to accomplish this. Producing viable, healthy, sterile males may be a feasbile means of mosquito control.http://www.blogger.com/img/blank.gif

Do any of you have a problem with this? Is this playing "god" too much, messing with the reproduction of another species?


Females Can Control the Evolution of Male Handsomeness

Is there such a thing as too good looking for a guy? Does this work with humans? If a guy is too good looking, will he not attract as many women?

Summer Assignment: 8.2

Before we get to the articles this week, I thought that this was too funny not to share.
























Anyway, two related links this week about bird/dinosaur evolution.

Xiaotingia zhengi

Earliest Bird was Not a Bird? New Fossil Muddles the Archaeopteryx Story

A new discovery of a fossil which sits somewhere between feathered dinosaur/early bird has changed the position of Archaeopteryx from the earliest bird to more of a distant bird cousin, or maybe just a dinosaur with feathers that watched the birds evolve. Adding this new fossil to the evolutionary tree moves Archaeopteryx out of the bird lineage and into a group of dinosaurs along with the new discovery named Xiaotingia zhengi.



Most importantly, this new discovery illustrates an extremely basic and important aspect of science which is often lost in public education. Science is an ever-changing, fluid entity. Just because Archaeopteryx has been moved from the position of earliest bird, does not mean it is gone, or not an important fossil. And it certainly doesn't mean that evolution is wrong. Science is about putting forth hypotheses, and seeing if the data support them. If the data do not, they are discarded or revised. It is not correct to say that these hypotheses were "wrong." They simply reflected an earlier set of data. Science is full of examples of this.