Hormone-mimicking chemicals cause inter-species mating

Jul 11, 2012

Hormone-mimicking chemicals released into rivers have been found to impact the mating choices of fish, a new study has revealed. The controversial chemical BPA, which emits oestrogen-like properties, was found to alter an individual's appearance and behavior, leading to inter-species breeding. The study, published in Evolutionary Applications, reveals the threat to biodiversity when the boundaries between species are blurred.

The research, led by Dr Jessica Ward from the University of Minnesota, focused on the impact of Bisphenol A (BPA) on Blacktail Shiner (Cyprinella venusta) and Red Shiner (Cyprinella lutrensis) fish which are found in rivers across the United States. BPA is an organic compound used in the manufacture of polycarbonate and other plastics. It is currently banned from baby bottles and childrens' cups in 11 U.S. states.

"Chemicals from and pharmaceuticals frequently end up in rivers and BPA is known to be present in aquatic ecosystems across the United States," said Ward. "Until now studies have primarily focused on the impact to individual fish, but our study demonstrates the impact of BPA on a ."

The team collected individuals of both species from two streams in the state of Georgia. The species were kept separated for 14 days in tanks, some of which contained BPA. On the 15th day behavioral trials were undertaken as individuals from different tanks were introduced to each other.

The scientists monitored any physiological or signalling differences the individuals displayed, such as colour, as well as any during courtship, such as .

BPA disrupts an individual's , which controls the release of hormones. This impacts behavior and appearance, which in turn can lead an individual to mistake a newly introduced species as a potential mate.

This process poses long-term , especially in areas threatened by the introduction of invasive species. BPA and other hormone-mimicking chemicals can escalate the loss of native biodiversity by breaking down species barriers and promoting the invader.

"Our research shows how the presence of these manmade chemicals leads to a greater likelihood of hybridization between species," concluded Ward. "This can have severe ecological and evolutionary consequences, including the potential for the decline of our native species."

Explore further: New study charts the global invasion of crop pests

More information: Ward, J.L, Blum, M.J, Exposure to an environmental estrogen breaks down sexual isolation between native and invasive species, Evolutionary Applications, July 2012, DOI: 10.1111/j.1752-4571.2012.00283.x

Related Stories

Paper money worldwide contains bisphenol A

Aug 10, 2011

The cash register receipts that people place near paper money in billfolds, purses, and pockets has led to a worldwide contamination of paper money with bisphenol A (BPA) — a potentially toxic substance ...

France sees labelling of contested chemical BPA

Sep 27, 2011

France's ecology minister on Tuesday said she would seek labelling requirements for food containers made with bisphenol A (BPA) after a watchdog agency sharpened its concern about this chemical.

BPA exposure effects may last for generations

Jun 15, 2012

Exposure to low doses of Bisphenol A (BPA) during gestation had immediate and long-lasting, trans-generational effects on the brain and social behaviors in mice, according to a recent study accepted for publication in the ...

Recommended for you

New study charts the global invasion of crop pests

14 hours ago

Many of the world's most important crop-producing countries will be fully saturated with pests by the middle of the century if current trends continue, according to a new study led by the University of Exeter.

Zambia lifts ban on safari hunting

16 hours ago

Zambia has lifted a 20-month ban on safari hunting because it has lost too much revenue, but lions and leopards will remain protected, the government said Wednesday.

The devastating spread of the mountain pine beetle

23 hours ago

When the mountain pine beetle began blazing a path across forests in British Columbia and Alberta, nobody could have imagined the extent of the damage to come. But as the insect devastated pine forests and ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

Bowler_4007
3 / 5 (1) Jul 11, 2012
some guy on facebook went straight to mentioning 'horse porn' funny to say the least lol (the porns not funny btw, thats just wrong) as presumably he only looked at title