The introduction to this series can be found here.
Summary: Genetic evidence shows that various Pleistocene populations interbred, including humans, Neanderthals and Denisovans. Is it possible to know whether these could have occurred in pair-bonded relationships? What were the evolutionary origins of pair-bonds in hominins, or are single explanations too simple?
Paleoanthropologist John Hawks created this great infographic that summarizes what we know about ancient human interbreeding, based on recent genetic discoveries (this link to his site has a larger version). The graphic shows that several archaic populations mated with each other, although likely at low rates, including modern humans with Neanderthals and Denisovans. There are also a couple of mystery populations in the mix, whose existence is known solely based on the DNA they left behind. Very cool stuff.
Who Interbred with Whom in the Pleistocene. (Figure by John Hawks).
This is part 11 of a series on the evolution of human mating behavior. Please see the introduction here. P.s. Does anybody actually read of all this?
“When the gods gave people sex, say the !Kung, they gave us a wonderful thing. Sex is often referred to as food: just as people cannot survive without eating… hunger for sex can cause people to die.” (Shostak 2000: 237)
“sex can be many things to many people, including but not limited to a blend of personalities, social rules, desire, intimacy and performance, moral order and national image that speak to processes of sexual embodiment, varieties of sexual practice and the dynamics of culture.” (Donnan and Magowan, 2010: 175)
E unum, pluribus. (Out of one, many).
Genital-themed ashtrays from the Komaki Penis Festival in Japan. For humans, sex is more complex than just getting genitals together. (globalpost.com).
Last month, representatives in Montana debated whether to repeal an old law that made homosexual sex illegal in that state (the law was in fact overturned). Apart from the fact that private, consensual sexual behavior is still considered a matter to be legislated, there were other interesting developments from the discussion. A representative named Dave Hagstrom raised a deep question when he asked: “What is the purpose of sex?” I appreciate Hagstrom’s line of inquiry, as we could probably use more reflection on human sexuality. Unfortunately his own answer did not live up to the profundity of the question:
“To me, sex is primarily purposed to produce people. That’s why we’re all here. Sex that doesn’t produce people is deviate. That doesn’t mean it’s a problem, it just means it’s not doing its primary purpose.”
“You can’t have everything. Where would you put it?” – Steven Wright (comedian)
“It seemed like a good idea at the time.” – S.A. (neuroscientist, friend)
Lately, I keep seeing a recurrent theme in a number of widely different sources. It’s a concept taught in Economics 101, that of tradeoff and opportunity costs – money or time invested in one object or activity cannot be spent on another. A related concept, foundational to biology, is life history theory (LHT). In his book “Patterns of Human Growth,” the biological anthropologist Barry Bogin defined LHT as:
“the study of the strategy an organism uses to allocate its energy toward growth, maintenance, reproduction, raising offspring to independence, and avoiding death. For a mammal, it is the strategy of when to be born, when to be weaned, how many and what types of pre-reproductive stages to pass through, when to reproduce, and when to die.” (1999: 154)
you could be a winner at the game of life