Gathering the mind to answer the foot is as this hand is the introduction to the song,
each bay of reserve to the mountain of a peak it is the bridge that makes Mankind its long,
from a universe that galaxies beyond what is the basic form of human frame to shoulder this yawn,
most of a creek is in the rivers mild yet an ocean may wave to the sands as its verse,
many grass to such soil asking not the fertile what of the coil,
a snake from a sky to the egg touching pi it remains to be the gateway of thresholds to homes that be sighed.
However from this Earth to human mortality people have at-large discussed so many be lied,
their words of are sentence that describe only hell as heaven is only one in the bell?
What grace gave to human beings such an eye that the midterm to blindness just gave callous to heels,
did the mud dry?
Capture a moment and do not sigh pi as the counted have numbered sequence it's hi,
just on that moon of a galaxy boom mankind decided difference and then added three,
perhaps on the two a zero did count as a shift in the cloud to disguise what is right,
left to that shoulder of sunshine and light people have made more of field and tight,
kept from a man I cry some for tum yet that is the life of myself thus far bum,
yet again I request for the hearth of a best for I to the hugging of more than a kept.
Surely this minus of division be long mankind desires more than a raft and a wow,
seen in the darkness is not the lit man for I would like love just to hold that dear man,
this is an order that does not go against nature as nature is natural and so is this bit,
bridle to rein on myself for the lane as saddled to girth is my own leg of sigh as I am girl in this world of tau,
no bisque did lie into my life as a guise for man is as independent as a snake and a cove,
lagoon to this raise and the singing is base from opera to sonata the opus is vase,
long ago from the places that this earth held to frame came more from the lakes that said what is a date,
yes in such grace that my tears do run now as my cheeks are not flush with rum and rums cakes.
Shed not the disguise now as mankind is its eyes from basis to people their just in their sighed,
maybe that is the way of this world with making the country great in as pissed as their vows and their lists,
so anger may grab your loins that are song however should kindness be grasp of you're fall,
than cobble may scrape your elbow of mate but at least the variable will be more than grape,
wine is a grain not yet on the table as salt is its soil and corn sits a side,
funny how place settings silverware stun yet at the phone call so many do Paul,
a good sit for bread a better for read,
this is this country on Turkey and said!!
The out-dated idea that females are chaste and males are promiscuous needs to be thrown away
Once upon a time, animal courtship was thought to run something like a Barbara Cartland novel. The rakish males battle it out for a chaste female, who sits around choosing the prince charming to father her young. While her mate may sow his wild oats far and wide, she patiently tends her brood.
Notwithstanding a few counterexamples, these roles were thought to be largely the same across the animal kingdom: males were thought to be promiscuous, dominant and aggressive and the females chaste and passive. For many people, it was just the natural order of the world.
But have we been blinkered by our own cultural prejudices, casting animals in the kinds of roles we saw in the society around us? That is the view of a small but growing number of biologists. "It's almost like they are using this locker-room logic – counting which males 'score' the most," says Joan Roughgarden at the Hawai'i Institute of Marine Biology.
The dividing line between male and female is frequently blurred or easily crossedResearchers such as Roughgarden argue that it was a classic case of "confirmation bias". Many biologists were seeing what they wanted to believe, and then using the results to justify prevailing cultural norms. "You get this back-and-forth: science is reinforcing societal mores, and the mores are reinforcing what the science is saying," says Zuleyma Tang-Martinez at the University of Missouri – St Louis.
The result, Tang-Martinez and Roughgarden believe, is that scientists have often failed to recognise astonishingly diverse sexual behaviours across the animal kingdom. There are now myriad examples of animals that break the rules entirely – from intersex kangaroo to a fish with four separate "genders".
If they are right, we should rethink many of our assumptions about sex differences. As with humans, the dividing line between male and female is frequently blurred or easily crossed.
Darwin saw the same patterns – males being "passionate", females "coy" – across the animal kingdomDarwin's solution was "sexual selection": a form of evolution that comes directly from the challenges of reproduction.
When many males compete for a single female, each male has to show off his worth in some way; either through direct combat, or in a showy display that proves he would be the healthiest father for her young. The resulting arms race led to the evolution of ever more excessive traits in the males of certain species: hence the peacock's tale, which helps it to advertise its good health to the peahen.
Darwin saw the same patterns – males being "passionate", females "coy" – across the animal kingdom. Later, the evolutionary biologist Angus John Bateman argued that this could be explained through basic economics.
The bottom line is that males have evolved to be promiscuous and females have evolved to be choosyThis means the stakes of the mating game are much higher for a female, and so she needs to choose her gamble carefully. Meanwhile, the male has sperm to spare, letting him take a gamble wherever he chooses.
The female's investment is even greater if she has to spend time gestating and rearing the young, so she needs to make sure she chooses a mate who will give her young the best genes and the best chances of survival.
"The bottom line is that males have evolved to be promiscuous and females have evolved to be choosy – they should only mate with the best male," says Tang-Martinez.
Just like peacocks, female pipefish have evolved bright, colourful markings as a result of sexual selectionThe same kind of logic has since explained the behaviours of many different species, from dragonflies and grouse to baboons and elephant seals. Indeed, a seminal 1972 paper on the subject by Robert Trivers has now been cited more than 11,000 times, making it one of the most influential ideas in evolutionary biology.
True, there were always some exceptions. For instance, in certain species of pipefish the female actively courts the male, before "gluing" her eggs to her chosen mate. While she can swim off to find another partner, he spends time nourishing the growing young.
In this case the male invests more in the young than the female does. But such cases of "sex role reversal" were generally considered to be rare
They were also thought to be exceptions that proved the rule. Just like peacocks, female pipefish have evolved bright, colourful markings as a result of sexual selection. These females are also larger than the males, and form hierarchies of dominance determining who can access the "harem".
Still, in the vast majority of species, males were assumed to play the jock while the females waited patiently on the sidelines. This assumption is now under attack by some biologists, who wonder whether it has been shaped by prevailing cultural preferences.
Even that very first study of fruit flies has come under scrutinyFor instance, some researchers had argued that men are naturally funnier than women, with humour acting as a sexual display akin to bright, colourful plumage – even though any apparent sex differences could easily be the result of sexist stereotyping rather than evolutionary history.
Perhaps biologists just have not looked hard enough to truly understand the complex ways that males and females may interact.
"We haven't really asked any questions about how sexual selection may be acting on females," says Patricia Gowaty at the University of California, Los Angeles. "We know barely anything about what's going on in competitive arenas of females… and the people that have asked seem to think the only way it might act is the same way it does on males."
Even that very first study of fruit flies – the cornerstone of parental investment theory – has come under scrutiny. When Gowaty tried to replicate the results in 2012, she failed to find convincing evidence that the males benefited from being more promiscuous than the females.
Female lionesses may mate 100 times a day with a string of different partnersFor instance, the females of many bird species had been thought to be exclusively monogamous, with the female faithfully sticking with her chosen partner.
In fact, this could not be further from the truth. Female birds often have dalliances even when in a stable partnership. Among the fairy wren, for instance, just 5% of the clutches will have been fathered by a single mate.
As further evidence, Tang-Martinez points out that female lionesses may mate 100 times a day with a string of different partners. The same seemingly-indiscriminate lust can be seen in many species of primates: not just the famously sexually-active bonobos, but langurs, lemurs and capuchin monkeys. That's not to mention countless studies of beetles, crickets, salamanders, snakes, geckos and house mice.
In all these cases, the females simply do not sit around waiting for Prince Charming, as Bateman had proposed. But the idea that this overthrows Bateman's ideas is rather controversial.
It is dangerous to come up with simple explanations for all speciesA study published in February 2016 compared the behaviours of 60 different species, and it supports Trivers. "As far as our data go, it's true for [the] vast majority of species," says co-author Nils Anthes of the University of Tübingen in Germany – although he agrees there are many exceptions.
But even in this comprehensive study, Tang-Martinez points out that the overall differences between the sexes were rather weak: according to one measure, they were not even statistically significant.
Furthermore, the number of species studied was still relatively small, she says. The study also did not fully account for the fact that sex differences may change depending on circumstances – like the ratio of males and females within the population, which could influence how the individuals pair up.
In any case, Tang-Martinez is not suggesting that we should throw out the whole theory. Clearly, it is true for some animals. Instead, she thinks it is time to drop the more sweeping generalisations about male and female behaviour. "It is dangerous to come up with simple explanations for all species," she says.
When I got into it I was astonished by just how much variation there isHow, Roughgarden wondered, does biology account for such a huge population, normally considered an unfortunate footnote in scientific theory? "When scientific theory says something is wrong with so many people, perhaps the theory is wrong, not the people," she concluded.
The result was her 2004 book Evolution's Rainbow, which examined the multitudinous ways that sex is expressed in nature. It goes far beyond our black-and-white definitions of "male" and "female".
"As a biologist, you think there may be a couple – maybe as many as a dozen – of cases that depart from heteronormative binary," says Roughgarden. "But when I got into it I was astonished by just how much variation there is."
An intersex female bear actually mates and gives birth through the tip of her 'penis'However, the relevant genes can still be expressed in different ways. The result is that, within any species, many individuals will show characteristics of two sexes.
There are plenty of examples of hermaphrodite invertebrates: leopard slugs are one of many. But Roughgarden has also found that intersex individuals are common among mammals, including red kangaroos, tammar wallabies, Vanuatu pigs, and America's black and brown bears.
According to a 1988 study, between 10 to 20% of female bears have a penis-like structure in place of a vagina. "An intersex female bear actually mates and gives birth through the tip of her 'penis'," says Roughgarden.
These are extreme cases. But many other animals cannot be classified simply as "males" and "females", as if members of each sex will look and act according to the same template.
Among white-throated sparrows there appear to be two kinds of males and two kinds of femalesFor instance, the bluegill sunfish has three male genders, each of which reproduces in a different way. The largest, most aggressive males show off a flashy orange breast, and actively court females to lay eggs in their territory. In contrast, the smallest males are duller in colour and have no territory of their own, but will dart into one of the dominant male's territory's to fertilise some of his mate's eggs.
It is the medium-sized males who are the most surprising. They appear to actively court the larger males with a dance in the water. If the big male accepts their advances, they may then form a ménage a trois with an approaching female, with both males both fertilising her eggs.
Why would the larger male team up with the weaker partner in this way? One possibility is that his presence helps to reassure the female that the larger male is not too aggressive. For this reason, Roughgarden describes these medium-sized males as marriage brokers.
In other species, a range of "genders" may offer a greater variety of parenting styles.
A "cross-dressing" male with more feminine features is often described as "deceptive"The result is a number of different possible couplings, each dividing the responsibilities of parenting – such as feeding and defending the young – in a different way.
Roughgarden's book offers many similar examples among hummingbirds, wrasse and tree lizards, each showing a spectrum of genders.
There is also a growing list of species that engage in homosexual behaviours. With such variation, it begins to make less sense to discuss "male" and "female" behaviour as if it means the same thing for all species, or even all individuals within a species.
Even when biologists have noted these exceptions, they tend to describe them in pejorative terms, she says. For instance, a "cross-dressing" male with more feminine features is often described as "deceptive".
The living world is made of rainbows within rainbows within rainbows"Again, it's this locker-room story – you go to a bar, see this cute-looking girl, and it turns out to be a guy, so you feel fooled and taken advantage of," she says.
Still, Roughgarden thinks attitudes are changing, albeit slowly. Today, homosexual behaviour in animals is attracting more research, and she hopes the same will be true of sex and gender roles more generally. "There's just beginning to be a discussion about non-binary gender variation," she says.
By ignoring this variation, we simplify the story of evolution and neglect some of nature's most astonishing adaptations. As Roughgarden puts it: "The living world is made of rainbows within rainbows within rainbows."
This story is part of our Sexual Revolutions series on our evolving understanding of sex and gender.
Join over five million BBC Earth fans by liking us on Facebook, or follow us on Twitter and Instagram.
If you liked this story, sign up for the weekly bbc.com features newsletter called "If You Only Read 6 Things This Week". A handpicked selection of stories from BBC Future, Earth, Culture, Capital, Travel and Autos, delivered to your inbox every Friday.
No comments:
Post a Comment