Sperm Wars

Based on new evidence, it shouldn't be long before Las Vegas oddsmakers start accepting wagers on the intense battles that have now been observed within the sex organs of females. According to the March 19, 2010 issue of Science (available online only to subscribers; it is page 1443 in the print edition), sexual selection continues on in the most intimate of arenas in at least some species in which the females sometimes mate "more than once in quick succession, filling their reproductive tract with rival sperm that must compete for access to the unfertilized eggs." The Science article, by Elizabeth Pennisi, is entitled "Male Rivalry Extends to Sperm and Female Reproductive Tract." According to Pennisi, two recent studies have shown that the seminal fluid of some ants and bees contains "toxins that impede rival sperm." She also notes that some female fluids seem to counter these toxins. The studies cited in science indicates that "the competition between males continues in a very fierce way inside the female."

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The genesis of human cooperation

In the special "Origins" issue of Discover Magazine, evolutionary anthropologist Michael Tomasello discusses some of his findings based upon his most recent book, Why We Cooperate. The article is not yet available online. The author of this article (Carlin Flora) opens her interview with Tomasello by pointing out that the vast majority of projects done in today's world are done in collaboration with others. What makes humans such collaborative beings? Actually, willingness to collaborate is a quality that clearly separates us from the other great apes, says Tomasello. He argues that the reason we cooperate so well with each other is our deep desire to help others and work with them toward shared goals. He was startled to find the degree of the "natural tendency" of young children (aged 1 to 3 years old) to cooperate with each other, but also to demand that newcomers to a group follow the rules of their games. Tomasello sketches out what he thinks is the origin of cooperative behavior

I think cooperative behavior started with obligate collaborative foraging, which is just a fancy way of saying that we need one another's help to get food. If we have to work as a team to get food, all of a sudden you're really important to me, and I am motivated to make sure you get your fair share so the you will want to team up again. Were interdependent.
Tomasello argues that the "second booster rocket of our evolution of cooperation" was the development of social norms-agreements about how to act.
Humans have conformity norms. In our studies we will show a kid how a game works, and then we'll have a puppet come in who plays the game wrong. The children will say "no, no, no! This is not how you do it! You do it like this!" But conventions apply only to "us" in the group; it is "we" who prepare our food in this way and dress in this way. It's part of our identity that we do it like this. In contrast to those people on the other side of the river; they talk funny, they dress funny, the discussing things and we don't care whether they behave in this way are not.
How powerful is the human instinct toward cooperation? "We conduct our wars with armies that are highly cooperative." The big question for Tomasello is whether we can scale up our willingness to cooperate, which evolved in small groups. We haven't completely ruined the world yet, and "we are still here."

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