Armed beetles find a mate, whatever their size

Mar 27, 2008
L. japonicus
Librodor japonicus. Credit: Kensuke Okada

One species of armed beetle is proving that size doesn’t necessarily matter when it comes to finding a mate. The creature’s ‘pulling techniques’ will be revealed in the April edition of the Royal Entomological Society’s Ecological Entomology journal.

In the world of armed beetles, biggest is usually best, as males often fight for mating rights and those with the largest jaws beat off the competition. However, this is not always the case with one particular species.

Researchers at Okayama University in Japan have been monitoring the mating habits of large, medium and small Librodor japonicus males, and found that this particular species adopts a different tactic to finding a mate depending on the size of certain body parts.

The largest male beetles wait for females at the feeding areas and fight for the right to mate – the males with the biggest jaws stand the best chance of winning. The medium sized beetles which are too small to beat the bigger males have developed relatively bigger wings than their larger counterparts, and they use these to search for the feeding sites which are unoccupied by large males.

The smallest male beetles have adopted a completely different tactic – they stay at the feeding sites with the big males, and attempt ‘sneaky matings’ with females behind the bigger male’s backs. What’s more, these males have relatively larger testes and produce sperm that is more competitive than the bigger males.

The L. japonicus beetles have ensured that, through their size-determined mating tactics, they all have a chance of finding a mate, and sometimes with no fighting involved.

Researcher Takahisa Miyatake said, "Although other studies of armed beetles have observed 2 different sizes of males, we have shown that males can adopt up to three different behavioural tactics to improve their mating success."

Source: Wiley

Explore further: The ABC's of animal speech: Not so random after all

add to favorites email to friend print save as pdf

Related Stories

Report: NSA eyed preset strikes in cyberattacks

20 minutes ago

The National Security Agency secretly planned a cyberwarfare program that could automatically fire back at cyberattacks from foreign countries without any human involvement, creating the risk of accidentally ...

Towards more efficient solar cells

1 hour ago

A layer of silicon nanocrystals and erbium ions may help solar cells to extract more energy from the ultraviolet (UV, high-energy) part of the solar spectrum. Experimental physicists from the FOM Foundation, ...

Recommended for you

The ABC's of animal speech: Not so random after all

1 hour ago

The calls of many animals, from whales to wolves, might contain more language-like structure than previously thought, according to study that raises new questions about the evolutionary origins of human language.

Manatees could lose their endangered species status

11 hours ago

About 2,500 manatees have perished in Florida over the last four years, heightening tension between conservationists and property owners as federal officials prepare to decide whether to down-list the creature to threatened ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

HeRoze
not rated yet Mar 27, 2008
omg-lmao. whew.
I know this is serious, but man... i'm cryin here.