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Gawping excuse: Study found men's wandering eye is the result of evolution and their urge to reproduce with multiple partners

Gawping excuse: Study found men’s wandering eye is the result of evolution and their urge to reproduce with multiple partners

นักค้นคว้ามหาวิทยาลัยกลาสโกว์และสเตอร์ลิงของอังกฤษ พบว่าสตรีไม่ต้องไปโทษใครกับการที่พวกผู้ชายมักจะลูกตาไม่ค่อยอยู่กับที่ ชอบทำตาเจ้าชู้สอดส่ายเรื่อยไป เพราะสาเหตุมาจากวิวัฒนาการที่เพศผู้ต้องการจะผสมพันธุ์ เพื่อจะได้ขยายพันธุ์ให้แพร่หลายออกไป

พวกเขารู้ว่าจากประวัติการวิวัฒนาการของสตรีนั้น พวกเธอมักจะชอบใบหน้าที่คุ้นตาว่าน่าดู ในขณะที่บุรุษมักจะถือว่าใบหน้าที่แปลกออกไปมีเสน่ห์ นักวิจัยได้รู้จากการทดสอบกับกลุ่มผู้หญิง 83 คน และผู้ชาย 65 คน โดยการให้ดูรูปสุภาพบุรุษและสุภาพสตรีอย่างละ 5 คน และขอให้คะแนนตามความสวยงามด้วย และให้ทำแบบเดียวกันอีกรอบหนึ่ง

นักวิจัยพบว่าพวกผู้ชายในรอบที่สองจะกลับให้คะแนนรูปของคนเก่าต่ำลง เพราะรู้สึกว่าคนเก่าสวยและมีเสน่ห์น้อยลง  ต่างกับพวกผู้หญิงกลับให้คะแนนรูปผู้ชายคนเดิมสูงขึ้น.

ที่มา : ไทยรัฐ  1 กรกฎาคม 2556

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Familiarity: Women were more likely to find a man attractive if they recognised his face, the study found

Familiarity: Women were more likely to find a man attractive if they recognised his face, the study found

Off the hook: Men can’t help staring at other women because they have ‘evolved to increase their reproductive success’

  • Men found familiar women less attractive than pictures of unknown faces
  • Women, however, found men more attractive the more familiar their face
  • Study concluded that men’s wandering eye is due to evolution and helps ensure a man has plenty of offspring

By PAT HAGAN

PUBLISHED: 15:08 GMT, 26 June 2013

If you frequently catch your man’s eyes wandering when a pretty woman passes by, don’t blame him – it’s all down to evolution.

New research shows that while women are drawn to male faces that look familiar, men are more likely to rate someone they have never seen before as more attractive.

Psychologists came up with the findings after showing men and women pictures of dozens of different faces. The more women in the study saw pictures of the same man’s face, the more attracted they were to him.

But the men who took part rated the women as less attractive when they saw them for a second time.

Researchers believe the reason may be that men have evolved to maximise their reproductive success by mating with as many partners as possible.

The findings, by researchers at the University of Stirling and the University of Glasgow, shed new light on the way the sexes perceive facial familiarity.

Previous studies looking at how humans are drawn to friends and partners found we are more likely to warm to others with familiar or ‘average’ faces that match the size and shape of the general population.

But the latest research suggests the extent to which that initial attraction lasts differs greatly between the sexes.

The researchers carried out a series of studies to measure changes in attractiveness.

In one, 83 women and 65 men were presented with pictures of five men and five women, one at a time.

They were asked to score them for attractiveness on a seven-point scale.

The participants were shown the pictures a second time but alongside another headshot they had not seen before to provide a distraction.

The results, published in the Archives of Sexual Behaviour, showed women judged the men’s faces as more attractive second time round because they were familiar to them.

But while the men also gave the male images a higher score, they found the women less attractive when there was a new female image to look at.

In a second similar study, volunteers were shown facial images and asked to rate them according to trustworthiness and sexiness.

When the experiment was repeated to see how scores changed, the women rated the familiar male faces as even more trustworthy and sexy but the men slashed their sexiness ratings for women.

Researchers say the results may be partly explained by the so-called Coolidge effect – where men are aroused by the novelty of a new sexual partner more than women.

It’s named after an anecdote attributed to 30th U.S. President Calvin Coolidge.

During a farm visit, when his wife was told there was only one cockerel and many hens because the cockerel would mate several times a day, she reportedly said: ‘Tell that to Mr Coolidge’.

When the president asked if it was with the same hen each time and told no, he allegedly said: ‘Tell that to Mrs Coolidge.’

In a report on their findings the researchers, led by psychology research fellow Anthony Little from Stirling University’s School of Natural Sciences, said: ‘Men found female faces they had already seen as less attractive and less sexy, especially for short-term relationships.

‘There is a tendency for males to pursue a large number of partners as they can dramatically increase their reproductive success by mating with multiple females.’

Psychologist Dr Jane McCartney said it was an evolutionary trait that many men are programmed to have sex with numerous partners.

‘Men are geared to reproduce as much as possible and some take full advantage of that.

‘But from a practical point of view it doesn’t make sense to go round having lots of children with different women.’

SOURCE: www.dailymail.co.uk

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ต้องทนปวดหลัง รับกรรมเดิน 2 ขา

thairath130301_001ความก้าวหน้าในการวิวัฒนาการของมนุษย์ จนสามารถเดิน 2 ขาตั้งตัวตรงได้ ทำให้คนสมัยนี้ ต้องรับกรรมจากโรคปวดหลัง และอื่นๆ มาจนเดี๋ยวนี้

มองในแง่วิวัฒนาการแล้ว มนุษย์จัดว่าก้าวหน้ายิ่งกว่าสัตว์เลี้ยงลูกด้วยนมทั้งหลายหมด จนถึงกับมีปริมาณใกล้จะ 7 พันล้านคนในขณะนี้

นักมานุษยวิทยาอลัน มานน์ มหาวิทยาลัยปรินซ์ตันของสหรัฐฯกล่าวว่า “เราต้องรับกรรม เพราะการวิวัฒนาการของมนุษย์อยู่ แม้ว่าเราสามารถเดินตัวตรง ทำให้มือว่างใช้เครื่องมือได้ แต่ก็ทำให้กระดูกสันหลังของเราต้องรับภาระหนัก ในการต้านกับแรงโน้มถ่วง ซึ่งอาจเป็นสาเหตุที่ผู้คนส่วนมากบ่นปวดหลังไปตามๆกัน”

เขาเปรียบเทียบเพื่อให้เห็นภาพของกระดูกสันหลัง ที่ต้องรับภาระหนักว่า “เหมือนกับเอาถ้วยกาแฟพร้อมกับจานรองซ้อนต่อๆกันหลายๆชั้น แล้ววางหนังสือเล่มหนาๆ ไว้ข้างบน” และชี้ว่ากระดูกสันหลังจะต้องดัดตัวโค้งแอ่นเพื่อเลี้ยงน้ำหนัก

อยู่เสมอ อาจทำให้เป็นหลังคดชนิดแอ่น หรือกระดูกสันหลังโกงคดได้ และมนุษย์เราเป็นสัตว์เลี้ยงลูกด้วยนมชนิดเดียว ที่กระดูกสันหลังแตกหักขึ้นเองได้.

ที่มา : ไทยรัฐ 1 มีนาคม 2556

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mnn130215_001
Aches and pains: You can thank evolution for them

While walking upright freed up our hands for tool use, the resulting stresses from gravity on the human spine may have led to unique back pains.

By Charles Choi, LiveScience Fri, Feb 15 2013

BOSTON — Bad backs, dangerous childbirths, sore feet and wisdom teeth pains are among the many ailments humans face from evolution, researchers say.

In an evolutionary sense, humans are by far the most successful primates on the planet, with a world population close to 7 billion. Humanity owes this success to a number of well-known adaptations, such as large, complex brains and walking upright on two feet. However, there are downsides to these advances as well.

“We’re dealing with the scars of human evolution,” anthropologist Alan Mann at Princeton University told LiveScience.

For instance, while walking upright freed up our hands for tool use, a key factor in human success, the resulting stresses from gravity on the human spine may have led to unique back pains.

“We’re the only mammals that spontaneously fracture vertebra,” anthropologist and anatomist Bruce Latimer at Case Western Reserve University told LiveScience.

Latimer and other scientists detailed their findings on human evolution today (Feb. 15) here at the annual meeting of the American Association for the Advancement of Science.

Achy backs
To underscore the challenges the human spine faces because of humanity’s upright posture, Latimer compared the spine to a tower of 24 cups and saucers, with each cup representing a vertebra in the spine and each saucer one of the disks between each vertebra. [10 Wacky Facts About Humans]

“Then take a book like a dictionary and put it on top. This is the head. If you are really careful, you can balance it — otherwise there’s a lot of porcelain on the ground,” Latimer said. “Then imagine taking this and putting in all the curves that you naturally have in the spine. I could give you all the duct tape in the world, and you still couldn’t possibly balance it.”

As the spine developed curves to keep balanced while upright, it can become stressed at certain points. This can result in conditions such as lordosis, or swayed backs; kyphosis, a rounded upper back or hunch back; and scoliosis, a sideway curve in the spine.

In addition, the spine also suffers from how people walk — one foot forward at a time with the opposite side arm swinging in step.

“This creates a twisting motion that, after millions of twists over time, the discs between the vertebrae begin to wear out and break down, resulting in herniated discs,” Latimer explained.

Evolving from four-footed to two-footed walking has also resulted in a host of foot problems, such as flat feet and bunions. Fossil evidence suggests that humans have suffered foot problems such as high-ankle sprains as far back as 3.5 million years ago, not just because of more recent, sedentary lifestyles.

“The fossil record is revealing that a lot of the foot problems we have now can be traced back to our past,” functional morphologist Jeremy DeSilva at Boston University told LiveScience.

Pain in the teeth
The dramatic boost in brain size that helps set humans apart the most from the rest of the animal kingdom also has led to problems many now experience with wisdom teeth, the third set of molars that get their name from the fact that they erupt as people approach the end of adolescence. [10 Odd Facts About the Human Brain]

“Our brains expanded to more than triple of our ancestors. As a result, the architecture of the braincase has changed,” Mann said.

This often leaves wisdom teeth no room to grow, causing them to erupt in painful ways.

“Evolution doesn’t produce perfection,” Mann said.

The problems that wisdom teeth can pose likely explain why genetic mutations that prevent their development have spread in human populations.

“The population with the highest frequency of missing third molars are the Inuit in the Arctic of North America, where it’s as high as 44 percent,” Mann said. Intriguingly, the only human population that apparently always had wisdom teeth in adulthood were the Neanderthals, he added.

Designing a human body
The evolution of upright walking has also made childbirth much riskier for humans than any other primate.

“If you want to look for examples of how we’re not the result of intelligent design, you don’t have to go far — just look at the complicated, uncomfortable way we have babies,”anthropologist Karen Rosenberg at the University of Delaware told LiveScience.

The complex societies that humans have developed now help women survive childbirth.

“We mitigate these problems with midwives, obstetricians, attendants of any sort in the childbirth process,” Rosenberg said.

“If an engineer were given the task to design the human body, he or she would never have done it the way humans have evolved,” Latimer said. “Unfortunately, we can’t go back to walking on four feet. We’ve undergone too much evolutionary change for that — and it is not the answer to our problems.”

SOURCE : www.mnn.com