How housework kills Komodo dragons
SMALL PRINTS:Lizard-killing housework, getting up close and personal with bedbug antics and corals that summon bodyguard fish were among the curious scientific animal tales to make the headlines in 2012.
Let’s start with the lizards: a study out in October linked the physical demands of “extreme housework” – such as building nests and guarding eggs – with the slower growth and substantially shorter lifespan of female Komodo dragons, compared to males.
The research, published in PLOS One, analysed the growth of individual Komodo dragons in eastern Indonesia.
“Males and females start off at the same size until they reach sexual maturity at around seven years of age. From then on females grow slower, shorter and die younger,” said researcher
Dr Tim Jessop from the University of Melbourne in a release.
“The sex-based difference in size appears to be linked to the enormous amounts of energy females invest in producing eggs, building and guarding their nests.”
Of course, humans are different to lizards, but the female Komodo’s plight still sounds like a useful excuse to trot out if you want to take it easy this Christmas.
That said, if you decide to take to the bed instead of doing the housework, be aware of what could be sharing it with you.
Bed bugs (Cimex lectularius) have annoyed humans for millennia, and in some parts of the world they are on the rise.
A lab study in Denmark sought to get real-time data on the signalling chemicals the creatures produce, particularly during mating behaviour. So the researchers not only collected the volatile chemicals in order to analyse them, but they also filmed the bed bugs in action.
The results, also detailed in PLOS One, suggest that the insects produce “defensive emissions” when they want to avoid copulation.
And bed bugs aren’t the only ones sending out signals – the coral Acropora nasuta can seemingly summon help from “bodyguard” fish if it is threatened by toxic seaweed.
A study at Georgia Institute of Technology discovered the alarm system by exposing the coral to Chlorodesmis fastigiata algae.
Within minutes, two species of goby fish were on the case, removing the offending seaweed.
Experiments showed that the fish were responding to a message from the coral itself, and that by eating it, some fish themselves became less of a catch for predators.
“Within minutes of seaweed contact, or contact from only seaweed chemical extract, the coral releases an odour that recruits gobies to trim the seaweed and dramatically reduce coral damage that would otherwise occur,” wrote the study authors in Science last month.
“In turn, chemically defended gobies become more toxic after consumption of this noxious alga.”