Monogamy and relative sizes of males and females

This story, about the discovery that homo erectus apparently did not descend from homo habilus, but existed concurrently, broke over a week ago, but I didn't get a chance to read it until just now.

I wasn't terribly surprised. When I did some brief research on evolution to try fortify myself with specific facts in discussing, with P-Life, why observant Jews should not dismiss evolution, there were already hints that some scientists felt that way. It seemed to be a growing trend, as more and more fossils were found and classified as either homo habilus or homo erectus. Scientists still agree that one or the other of them evolved into homo sapiens, i.e., us. I really, really don't understand why some people read this news story and immediately felt justified in saying, "See, evolution isn't right after all!" Anyway, I don't want to get into that discussion again.

What I thought was interesting in this AP article were these lines:
That caused researchers to re-examine the 30 other erectus skulls they have and the dozens of partial fossils. They realized that the females of that species are much smaller than the males -- something different from modern man, but similar to other animals, said Anton. Scientists hadn't looked carefully enough before to see that there was a distinct difference in males and females.

Difference in size between males and females seem to be related to monogamy, the researchers said. Primates that have same-sized males and females, such as gibbons, tend to be more monogamous. Species that are not monogamous, such as gorillas and baboons, have much bigger males.

Among modern humans, men and women are of roughly the same size. Although the average male is, of course, taller and heavier than the average female, there is some overlap in the middle of the spectrum.

I'm not entirely sure why I feel this way, I think there's something nice about monogamy being more pervasive in species in which males and females are closer in size. I guess that I associate monogamous societies as ones in which men and women have more equality, and so the fact that males and females are also closer in size where monogamy exists jibes nicely. It just seems fitting, somehow.

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I'm sorry that I've been posting so irregularly. Since I started blogging, I have never had so many contiguous months with so few posts. In looking back over the past few months, I see that my blogging quantity, and possibly quality, declined precipitously starting in May. (Actually, June had some very nice posts, so perhaps I shouldn't leap to make that claim.) I attribute this to the news I got in May of my grandmother's very short life expectancy, followed by my last visit to see her at the end of May, and her subsequent death at the end of June, followed by going to the funeral and shiva. (I wrote this post in mid-May, when it became fully apparent that my grandmother did not have long to live. I wanted to thank her, while she was still alive, for at least some of the things that I've received from her. Likewise, this post had been languishing in the draft box since Pesach, and I finally polished it up and published it because I knew that it would be weird to publish it after my grandmother died, when I would be consumed with sadness and thoughts about the entirety of her life, and not necessarily little details about yom tov in her house over the past few years. Finally, this was, in many ways, meant to be a tribute to my grandparents for the incredibly mind-expanding summers that they provided for us. I wanted my grandmother to know how I felt, and, in fact, my mother read this post to her on one of her last "good" days, a week before she passed away.)

Oh, yes. And then there was the subway incident, which took place the day after I returned from visiting my grandmother for the last time. July and August were particularly strenuous months at work. And the moving...oh, the moving! I am still nomadic, but hope to be settled into my new home sometime this week.

So, what I'm trying to say is, "I am still here and I am still thinking interesting things once in a rare while, I just don't have the energy to sit down and write thoughtful posts right now." I hope you will forgive me and remain loyal readers (all three of you!).

1 comment:

smoo said...

"I guess that I associate monogamous societies as ones in which men and women have more equality..."

It is not uncommon to approach this topic from the perspective of leveling the unequal playing field. But nature has its own unevenness which sometimes is unexpectedly skewed in favor of the female over the male. One such instance is elaborated on in Our Inner Ape by Frans De Waal. It has great insights into our nature based on our common ancestry. In it, he describes the bonobos, female bonobos are no stronger than males (p.88) yet bonobos have a female ruled system and they are very promiscuous. Even though there is a F:M ratio of 1:1 it isn't because they are monogamous nor do they have stable M-F relationships as we do but their bonds are mother to sons with top females securing higher places for their sons (p.68-9). What is interesting is that the female size is roughly what it is for human female to male, ie approximately 85% of the male size even though the bonobos are ruled by a top female (p.10)!

Equality, I think is a very human construct, and very out of balance with nature (for the most part).

Something to chew on.