U.S. Teen Sex Declines Sharply Over Past 25 Yrs

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Kinky sex takes place in many coffee beans before they are roasted, suggests a new study on coffee berry borers, which are the most serious pests of coffee plants worldwide.


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Creatures That Have Sex in Your Coffee: Photos

Kinky sex takes place in many coffee beans before they are roasted, suggests a new study on coffee berry borers, which are the most serious pests of coffee plants worldwide. These small beetles, native to Africa, live much of their lives in coffee beans, according to the study, which is published in the Journal of Insect Behavior. It's little wonder that the fast-living beetles, Hypothenemus hampei , have the nickname "Ferrari." Weliton Dias Silva of the University of São Paulo and his colleagues determined that females of this tiny beetle "have to be copulated by their sibling males before leaving the native coffee fruit to improve their chances of successful colonization." Females are about .07 inches long, while males are only about .06 inches long.

Daniel Karp

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Home for the coffee berry borer are the seeds of coffee fruit, which are commonly known as coffee beans. Dias Silva and his colleagues report that the insects find their coffee bean homes after sniffing out chemicals released by coffee plants. Like many gourmet coffee drinkers, they prefer beans of Coffea arabica .

Stanislaw Szydio, Wikimedia Commons

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Males are always much smaller than females, so they are referred to as "dwarves." "After copulation with their few dwarf, flightless male sibs, H. hampei females often leave the coffee berry in which they developed," Dias Silva and his team share. Females sometimes don't even wait around for males. In addition to their incestuous sex, they can also reproduce all on their own. This phenomenon, also seen in certain snakes, sharks and other animals, is known as parthenogenesis.

L. Shyamal, Wikimedia Commons

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The telltale sign that a beetle has been in your coffee are minute holes that females bore into beans. Usually the beans will be eaten away by larvae, which hatch from eggs laid by the females. Another clue is a coffee bean that seems hollow inside. Video: Goodbye Plain Joe, Hello ... Buttered Coffee?

L. Shyamal, Wikimedia Commons

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Worldwide, the coffee berry borer causes an estimated $500 million in losses among coffee growers, according to the USDA. The coffee industry has an economic value exceeding $70 billion annually, with over 20 million coffee-farming families producing coffee in more than 50 countries. "The insect can cause coffee farmers to lose up to 20 percent of a crop and reduce the price by 30 to 40 percent," said Ted Lingle, executive director of the Specialty Coffee Association of America. He continued, "Damage from the borer fruits hurts every coffee-producing country in the world." Genes Determine How Coffee Affects You

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One of the major findings of the new study is that females are 15 days old when they leave their coffee bean homes, flying away to colonize another plant. Males don't leave, so one of your roasted coffee beans could have one or more burnt-to-a-crisp male coffee berry borers in it. Clearly these insects are bad news for coffee growers, so researchers are constantly seeking ways to control the pests. Vega mentioned that one technique is to "fight back with fungi" that the beetles hate. Another method is to introduce nemotodes, which are microscopic simple worms. The minute worms parasitize female coffee beetle borers, preventing them from laying many eggs. "Nonparasitized insects laid an average of 10 eggs, but parasitized borers laid just under 2 eggs on average," Vega explained. Coffee Fungus Jolting Java Market

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While most infested beans are removed from the market, some invariably wind up in the roaster. Close inspection of most roasted beans reveals that they have been affected by coffee berry borers and possibly other insects. Coffee Genome Reveals Secrets of a Good Brew

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Coffee plants attract a wide variety of insects, and not all of them are as damaging as the fast-living coffee berry borer. Richard Zack and Peter Landolt at Washington State University are studying biodiversity associated with coffee plants. They traveled to Guatemala and found an incredible number of bugs happily living on and around the plants. Zack and Landolt spotted 900 species of moths, yellow jackets, aquatic insects, cicadas, gigantic horned Goofa beetles, brown jewel beetles prized by collectors in Japan and Europe, and more. So the next time you enjoy a cup of coffee, consider all of the insects that interacted with the beans, including some that associate coffee with fast and furious sex.

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Less than half of U.S. teenagers today are sexually active, far fewer than in the late 1980s, a U.S. government report said Wednesday.

Aside from the pleasurable feelings that come with it, evolutionarily speaking why do humans have to have sex to keep the species going when it doesn't seem the most efficient way to go?

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The findings are based on survey data spanning 1988 to 2013, called the National Survey of Family Growth, offering a glimpse at national estimates of sexual activity, contraceptive use and childbearing among teenagers aged 15–19.

“In 2011–2013, 44 percent of female teenagers and 47 percent of male teenagers aged 15–19 had experienced sexual intercourse,” said the report by the National Center for Health Statistics.

“The percentage has declined significantly, by 14 percent for female and 22 percent for male teenagers, over the past 25 years.”

In 1988, 60 percent of teenage boys and 51 percent of teenage girls were sexually active.

The lowest points were seen in the 2006-2010 range for females, with 43 percent saying they had had sex at least once.

For males, the lowest number was 46 percent in 2002.

When researchers separated the data by age, they found that 15-year-olds were the least likely to have had sex (about 15 percent).

The likelihood of sexual activity increased over time. Almost two in three 19-year-olds have experienced intercourse at least once, the report said.

The declining rates of sexually active youth coincide with previous research that has found a big drop in the teen birth rate.

In 2013, the teen birth rate of 27 per 1,000 people was less than a third of the historically highest rate in 1957, when it was 96 per 1,000.

Contraception use has stayed about the same in recent years, with condoms still being the most popular choice followed by withdrawal and oral contraceptives, the report found.

“In 2011–2013, 79 percent of female teenagers and 84 percent of male teenagers used a method of contraception the first time they had sexual intercourse,” it said. ”The percentages have not changed over time.”

Emergency contraceptive use has climbed from eight percent of girls in 2002 to 22 percent in 2011–2013.

By age 17, girls who did not use a contraceptive method the first time they had sex were five times as likely to become pregnant as girls who did use some kind of method.

This report is based on data from 1,037 females and 1,088 males in the United States.