Tuesday, May 1, 2007

Dani's New & Hot (Week 5)

Animal Extinction - the greatest threat to mankind.
The article can be found here. It's fairly long, but here's a summary...

Scientists agree that there have been 5 known great extinction events throughout the history of the earth. We are currently living in the 6th, the Holocene extinction event. While the background extinction rate is approximately one species per million per year, with new species evolving to take the place of those extinct, according to Harvard biologist, Edward Wilson, half of all plant and animal species living today will be extinct by 2100. This is almost an 100 fold increase over the background extinction rate. The World Conservation Union's Red List (a list measuring the population status of the world's 1.5 million scientifically identified species) show that approximately 40% of examined species are in danger of extinction. Not only are individual species at risk of extinction, but higher taxa are in danger as well. For instance, the 300 million year old Amphibia class, which has out survived most dinosaurs, is dying off at alarming rates. Most of its members are losing the battle against rapidly changing climates caused by human environmental assults.

Why is this happening? The short answer is that human pollution, deforestation, hunting, etc. is changing climates and wildernesses so quickly that species are unable to adapt. And as we all learned in high school biology (and "Pocahontas"), all the organisms in the world are interwoven in a fragile fabric connecting all life, and a disruption in one fiber causes a chain reaction to occur.

So what is the solution? The article suggests "rewilding" or "megapreservation" as a potential way to remedy the effects of artifical environment and climate destruction. The goal is to connectexisting wild life preserves by "megalinkages", providing animals the ability to roam and thus to increase the biodiversity of each wildlife area. The article also brings up an interesting point in that international border divisions cage animals in and decreases the resources available for wildlife survival.

So how does this relate to Darwin? Mainly, how can Darwin's theory of evolution be applied to organisms that are experiencing artificial pressures due to the increase in human dominance? Darwin's theory deals with NATUR(E)al selection, but how does this natural selection fare with human intervention?


On a lighter note, here are some people whose genes shouldn't be allowed to proliferate:
Darwin Dating
The website only accepts 18-35 year olds, because according to the makers of the site, a male's sexual drive maxs at age 18 and a female's at age 30, thus making "18-35 the perfect breeding bracket."
On second thought, this is a perfect example of natural selection...just not in these people's favor.

Darwin Quotes, from Voyage of the Beagle
1) Whilst talking about a group of escaped slaves in Rio de Janeiro, Darwin talks about how one of the women threw herself from a mountain in order to escape from being recaptured: "In a Roman matron this would have been called the noble love of freedom: in a poor negress it is mere brutal obstinacy."

2) More with Darwin & slavery in Rio de Janeiro: "While staying at this estate, I was very nearly being an eyewitness to one of those atrocious acts, which can only take place in a slave country. Owing to a quarrel and a law-suit, the owner was on the point of taking all the women and children from the men, and selling them separately at the public auction at Rio. Interest, and not any feeling of compassion, prevented this act. Indeed, I do not believe the inhumanity of separating thirty families, who had lived together for many years, even occurred to the person. Yet I will pledge myself, that in humanity and good feeling, he was superior to the common run of men. It may be said there exists no limit to the blindness of interest and selfish habit."

3) In the summer of 1832 while around Maldonado, Darwin writes, "The Molothrus pecoris is a Norht American bird, and is closely allied in general habits, even in such peculiarities as standing on the backs of cattle (as its name implieds), and in appearance, with the species from the plains of La Plata; it only differs in being rather smaller and of a dfferent colour, yet the two birds would be considered by every naturalist as distinct species. It is very interesting to see so close an agreement in structure, and in habits between allied species coming from opposite parts of a great continent." Could this have been where he started? Or did he add this in later after he had began to formulate this theory of evolution?

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