'Urine love story' has 1-0-2 of tilapia

Portuguese scientists discovered that male tilapia used their own urine to attract mates.

>>>Video: Fish build sand castle to attract mates

Researchers from the University of Algarve in Portugal have recently discovered a special point in the urine of Mozambique male tilapia (scientific name: Oreochromis mossambicus) - the ability to attract mates.

"The Mozambique tilapia is really an interesting fish," said lead researcher Tina Keller-Costa of the Marine Science Center at the University of Algarve .

Male tilapia know to dig a nest in the sand and consider it their own territory. They will fully protect the territory and only allow qualified female tilapia to "access" it. "

To compete for mates, male tilapia attempt to urinate into their territories. Experts have found that pheromones (substances used as chemical signals between individuals of the same species) contain quite a large amount of steroids - similar to progesterone - a female sex hormone in the land of male tilapia. .

The female tilapia lurking nearby will be able to smell pheromone and rely on it to find suitable partners.

Not only using urine, male tilapia also has a "guise" to summarize the partner, which is to create big belly.

Specifically, male tilapia will expand the bladder to store more urine. When they reach the target, they will force the urine out. This amount of urine will carry a large amount of steroid hormones to help your partner immediately collapse on the spot.

In contrast, male fish with small stomachs will be difficult to store large amounts of urine and the amount of hormones needed to find a satisfied partner.

Keller-Costa said: "This hormone is extremely important because it will be the factor that stimulates the release of eggs in the female perch. When the male sperm sperm is in harmony with the eggs in the female, will help the tilapia more easily pregnant ".

There are hundreds of tilapia in the world, so according to Keller-Costa "they are becoming successful invaders in many parts of the world, threatening freshwater ecosystems in rivers and lakes. ".

Therefore, experts say, the discovery of a mechanism to use pheromones to attract this partner will help them control the encroachment of other populations in the future.

The study was published in Current Biology.