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Why do men exist? Scientific study offers an explanation

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Since in many species, sperm is males’ only contribution to reproduction, biologists have long puzzled about why evolutionary selection, known for its ruthless efficiency, allows them to exist.

Now British scientists have an explanation: Males are required for a process known as “sexual selection” which helps species to ward off disease and avoid extinction.

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A system where all offspring are produced without sex — as in all-female asexual populations — would be far more efficient at reproducing greater numbers of offspring, the scientists said.

But in research published in the journal Nature on Monday, they found that sexual selection, in which males compete to be chose by females for reproduction, improves the gene pool and boosts population health, helping explain why males are important.

An absence of selection — when there is no sex, or no need to compete for it — leaves populations weaker genetically, making them more vulnerable to dying out.

“Competition among males for reproduction provides a really important benefit, because it improves the genetic health of populations,” said professor Matt Gage, who led the work at Britain’s University of East Anglia.

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“Sexual selection achieves this by acting as a filter to remove harmful genetic mutations, helping populations to flourish and avoid extinction in the long-term.”

Almost all multi-cellular species reproduce using sex, but its existence is not easy to explain biologically, Gage said, because sex has big downsides — including that only half of the offspring, the daughters, will produce offspring themselves.

“Why should any species waste all that effort on sons?” he said.

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In their study, Gage’s team evolved Tribolium flour beetles over 10 years under controlled laboratory conditions, where the only difference between populations was the intensity of sexual selection during each adult reproductive stage.

The strength of sexual selection ranged from intense competition — where 90 males competed for only 10 females — through to the complete absence of sexual selection, with monogamous pairings in which females had no choice and males no competition.

After seven years of reproduction, representing about 50 generations, the scientists found that populations where there had been strong sexual selection were fitter and more resilient to extinction in the face of inbreeding.

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But populations with weak or non-existent sexual selection showed more rapid declines in health under inbreeding, and all went extinct by the tenth generation.


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Trump ‘specifically pressured the president of Ukraine’: WSJ reporter explains bombshell report

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MSNBC anchor Nicolle Wallace on Friday interviewed one of the reporters behind a bombshell story on President Donald Trump and his interactions with Ukraine that are at the center of the whistleblower scandal.

"President Trump in a July phone call repeatedly pressured the president of Ukraine to investigate Democratic presidential candidate Joe Biden ’s son, urging Volodymyr Zelensky about eight times to work with Rudy Giuliani, his personal lawyer, on a probe, according to people familiar with the matter," The Wall Street Journal reported.

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This Friday, millions of people around the world are skipping school and work to demand action on climate change. According to reports, "global climate strikes" are currently taking place in over 150 countries, all designed to take place ahead of the opening of the United Nations General Assembly and the Climate Action Summit this coming Monday.

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WATCH: Barbara McQuade explains how she jailed mayor of Detroit — for same thing Trump did

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On Thursday, it was revealed that a whistleblower in the intelligence community has submitted a complaint about President Donald Trump's conduct with a foreign leader.

There was widespread speculation Friday on the nature of the complaint, but experts suspect it has to do with the president trying to extract opposition research on Joe Biden from the president of Ukraine. Recently, Trump's lawyer and friend Rudy Giulani traveled to the country to unearth dirt on Biden's son.

And experts are concerned that Trump promised the foreign leader a better relationship with the U.S. in exchange.

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