Toolbox
Digg It Reddit del.icio.us Save to Yahoo! bookmarks Save to Windows live Share on facebook Save to MySpace Slashdot it science news feed Add to google
- size +

Barnacles go to great lengths for sex

Unlike animals that travel long distances to breeding grounds under a wide range of conditions barnacles reproduce by extending impressively long penises to find and fertilize distant mates.
Unlike animals that travel long distances to breeding grounds under a wide range of conditions, barnacles reproduce by extending impressively long penises to find and fertilize distant mates.

Compelled to mate, yet firmly attached to the rock, barnacles have evolved the longest penis of any animal for their size - up to eight times their body length - so they can find and fertilize distant neighbours.
Unlike animals that travel long distances to breeding grounds under a wide range of conditions, barnacles reproduce by extending impressively long penises to find and fertilize distant mates. (Barnacles are hermaphrodites, so they can mate with male or female neighbours).

However, such long penises pose a major challenge because many inter-tidal barnacle species live under a wide range of wave conditions in which water velocities greatly vary. Consequently, individuals with penises well suited for mating in quiet waters may be poorly suited for copulating on wave-exposed shores.

The research, conducted at Bamfield Marine Sciences Centre on Vancouver Island by biological sciences graduate student Chris Neufeld and his supervisor Richard Palmer, compared intertidal barnacles (Balanus glandula) in calm, protected harbours, with those from wave-exposed shores.

"Our results showed that barnacles appear to have acquired the capacity to change the size and shape of their penises to closely match local wave conditions," said Neufeld.

"When wave action is light, a longer (thinner) penis can reach more mates, but at times of higher wave action, a shorter (stouter) penis is more manoeuvrable in flow and therefore can reach more mates." In addition, when moved from their original shore, barnacles could modify their anatomy to suit the surrounding water conditions.

Published in the Proceedings of the Royal Society B, the research suggests that sexual selection - competition with other males, female choice, sexual conflict between males and females - is not required to explain variation in genital form. In barnacles, this variation appears to be driven largely by the hydrodynamic conditions experienced under breaking waves.

"Put another way," said Neufeld, "barnacles select mates simply by being able to reach them, not by what they may look like when they get there."

Source: University of Alberta
» Next Article in General Science - Biology: Madagascar's tortoises are crawling toward extinction, groups say

would you recommend this story?

 

User Rating

4.2 out of 5 after 5 total votes
  • not at all
  • 1
  • 2
  • 3
  • 4
  • 5
  • highly

Leave a Comment or

Rank filter

Move the slider to adjust rank threshold, so that you can hide some of the comments.
Posted by nicolexue 02/19/08 21:21
Not rated yet.
STDromance.com is for those affected by STDs. According to the CDC, there are over 65 million Americans currently living with an STD, 19 million new STD infections each year, one in three sexually active men and women living with Herpes, and about 50% of all sexually active Americans affected by HPV. One-third of all single and dating Americans now exploring online personal ads (BusinessWeek, 2006) and niche dating has never been hotter.