Showing posts with label inclusive fitness. Show all posts
Showing posts with label inclusive fitness. Show all posts

Friday, June 14, 2019

Trust the Mother


One of the most divisive political issues is abortion rights. I am a scientist, and I can tell you that there is no single point in embryonic or fetal development in which the unborn child “becomes human.” It depends on the indicator that you use: heartbeat, brain activity, etc. all begin at different times. There are even three events that occur during “the moment of conception.” As a result, I have no scientific opinion about “when life begins.” Nor will I speculate about morality or politics. But I do have some scientific insights that you might find useful.

Love evolved. Love is, from the evolutionary point of view, the instinct for helping and protecting other animals in your species. Natural selection has favored animals that protect their offspring. In this way, they maximize their reproductive success. If you want to know more, search for information about inclusive fitness. The most famous examples are from insects such as bees, ants, and termites, and among mammals such as ourselves.

The strongest love in the natural world is the love between a mother and her offspring. It is a force of nature. If you get between a mother bear and her cubs, it might be the last thing you do. This is because the cubs are the mother bear’s entire genetic future. Human mothers are no less motivated to protect their young, including those not yet born, than any other species of mammal.

In the animal world, a mother’s love is, on the average, stronger than a father’s love. The reason for this is because the mother always knows which offspring are hers, but the father cannot be certain. Every ounce of effort that a mother puts into nurturing and defending her young is well spent, but for the father, there is the lingering subconscious question about whether the offspring are his. (“Mommy’s baby, Daddy’s maybe.”) Genetic tests, in humans and birds, show that some of the offspring in the nest or the home, which the father supposes to be his, are not. The offspring may not be the father’s entire genetic future. Most of us fathers love our children, but on the average, mothers love their children more.

And a mother loves her offspring, including those not yet born, more than politicians do.

Given that a mother’s love is the strongest love in the natural world, I believe we should trust the instincts of an individual mother. The idea that pregnant women are eager to kill their unborn children unless white men pass laws and tell them not to is ridiculous. Maybe we should trust the mother to make the right decision regarding her unborn offspring.

Sunday, March 1, 2015

Three Haldane-isms

Welcome to readers around the world; most are from America but apparently there are a few in France, Germany, and Russia. Bienvenu, Willkommen, and добро пожаловать.

As many of you know, John Burdon Sanderson Haldane (J. B. S. Haldane) was one of the most colorful figures in the history of biological science. A professor at Oxbridge (I forget which university it was), Haldane defined some fundamental concepts of biology; among other things, parallel to Soviet scientist Alexander Oparin, he speculated about the origin of life from inorganic molecules on a primordially anaerobic Earth (the Oparin-Haldane Hypothesis). Haldane always thought expansively.

I only recently realized that three of the most pithy insights of evolutionary biology came from Haldane. Here is a brief summary of them.

·        Inclusive fitness. An organism can be successful in terms of evolutionary fitness not only by having its own offspring but by promoting the offspring of its relatives, which carry some of that organism’s same alleles. Close relatives, such as siblings, carry more of the same alleles than do more distant relatives, such as cousins. The way the math works out, à la Hamilton, is that siblings have a relatedness of one-half, while cousins have a relatedness of one-eighth. That is, roughly speaking, two brothers or eight cousins would compensate for an organism’s inability to have its own offspring. Haldane knew this before Hamilton, and he quipped at a pub that he “would die for two brothers or ten cousins.” Most accounts say eight cousins, but John Maynard Smith (who might have actually been in the pub that day) said ten—that Haldane was just being on the safe side by allowing a margin of error for those cousins. This and other quotes can be found here.
·        The fossil record. Someone once asked Haldane what it would take for him to believe that the fossil record was produced by Noah’s Flood rather than by billions of years of sedimentation. He quipped that just one Cambrian rabbit fossil would be enough to make him question his evolutionary framework.
·        Biodiversity. Someone once asked Haldane what he had learned about God from his study of biology. Haldane, an atheist, could not give a straight answer to this question, nor did he launch into an anti-theistic tirade. He simply said that God must be “inordinately fond of beetles,” since there are over 350,000 species of them.

Most of us have heard all these things, but I was recently struck by the fact that all three of these insightful quips came from the same man.

Sometimes, academic disputes, especially at close quarters, can become pretty intense. The Christian apologist Clive Staples Lewis (C. S. Lewis) was Haldane’s colleague at whichever place it was. Haldane was pretty upset at Lewis’s writings. One of Haldane’s own essays, published in a communist newspaper, included “Anti-Lewisite” in the title, implying that Lewis’s writings were the equivalent of a kind of toxic gas (Lewisite) used in the Great War (now called World War I). I think most of us never knew about this dispute and even those of us who know about it think it quaint. Current disputes among colleagues will look pretty bland when seen from the perspective of the future, or when seen in a world context.