New research suggests that female animals learn to prefer the mates of certain males from other females. Sexual selection involves the evolution of traits such as the peacock’s long complex tail. These traits evolved not to increase an animal’s survival rate, but to increase its chances of attracting a mate. If you’re trying to escape from a predator, a heavy, multicolored tail will get in your way.
Males often compete for access to females because the male’s investment in offspring (often just sperm) is much less than the female’s efforts to produce eggs (which are larger than sperm), pregnancy, and possibly raising offspring. Therefore, it is much more expensive for a female to mate with a low-quality male than vice versa because the male can quickly move on to the next female.
This has led to the evolution of many sexually selected male traits and some very selective females in the animal kingdom. Historically, scientists have focused on interactions between men and often ignored how women shaped evolution. But researchers are now paying more attention to the surprising effects of female agency.
A new study by Florida State University in the US has developed a mathematical model that attempts to explain some of the gaps in sexual selection theories.
First, it’s helpful to understand what research shows about what makes a man attractive in the animal world. In terms of appearance, males with the largest cheek pads or flanks are the most attractive to female orangutans; Males with the longest “swords” repel female orangutans.
It’s not just about looks
Women choose a partner not only based on external characteristics. Male ringed lemurs with the strongest scent attract the most female attention. There are also many examples of more complex traits, such as the song and dance of birds of paradise or the crop circle patterns that male Japanese pufferfish make to impress females.
And men don’t always compete to be chosen by women. Male stalk-eyed flies choose females based on the distance between their eyes and find larger eyes more attractive.
Current theories of sexual selection suggest that animals choose mates based on traits that indicate good genes, such as a long, complex tail. A strong, masculine partner signals that he will give birth to healthy offspring.
On the other hand, animals that have a destructive trait but still survive are likely to have high genetic quality. There are also theories of sensory bias that suggest that marriage preferences are a byproduct of natural selection on the senses. For example, the hearing range of female Tungar frogs shifts towards lower frequencies; This coincides with their preference for lower sounds produced by larger males.
But none of these theories explain why there is so much variation in the traits of males of the same species, or why female preferences can change over time or within species.
rare sexual attraction
A new study investigated whether women’s choice of mates is based on observations of how more experienced women choose their mates. It is well known that animals can learn by observing others. For example, young crows learn to make basic stick tools by watching their parents.
Learning has also been demonstrated in mate selection; because females, when observing others with a male, are more likely to self-select that male or a male with similar characteristics. The researchers based their model on the proposed attraction hypothesis, in which inexperienced women compare the qualities of the man chosen by the experienced woman with the qualities of all men.
For example, if a female sees an experienced female with a brightly colored male, she may also seek out a brightly colored mate. This will cause bright coloration to become more widespread and variation to decrease. But the attraction hypothesis still cannot explain why there is so much disagreement between men.
The American study was the first to believe that women may not be able to read minds and may make mistakes when trying to copy other women. In the hypothetical example below, an experienced female prefers males with redder plumage and therefore chooses to mate with male number three. An inexperienced observer believes that the long tail of male number three makes him more attractive than his peers.
The researchers used computer simulations based on a mathematical model of a population in which males mate with many females. The model included males with two traits, each with only two variants (bright/dull color and long/short tail). Their model showed that when females select males for the same trait as an experienced female, those traits become fixed without change in the population. Females choosing a more characteristic male caused this rare trait to become more common and therefore less attractive.
This caused women’s preferences to change over time, rather than one attractive trait overriding others. We won’t know if this happens in real life until scientists do field studies. However, it is the first theory of sexual selection to explain how diversity in populations can be maintained.
My current celebrity crush is Ryan Reynolds because of his good looks and sense of humor. But now I wonder what others see in him: those eyes, that smile, or something else entirely? Source
Source: Port Altele
