A couple of items from BBC’s Nature feed have caught my eye. First, London’s Natural History Museum has hatched out an extremely rare butterfly genotype: a half male, half female. And I mean literally half and half.
[Luke] Brown built his first butterfly house when he was seven, and has hatched out over 300 thousand butterflies; this is only his third gynandromorph.
It is not only the wings that are affected, he explained. The butterfly’s body is split in two, its sexual organs are half and half, and even its antennae are different lengths.
“It is a complete split; part-male, part-female… welded together inside,” he told the BBC.
The genetic variation, which occurs in 0.01% of hatching butterflies, is a result of the sex chromosomes failing to separate during fertilization. Nor is it limited to butterflies, having also been observed in crabs, lobsters, spiders and chickens.
The other item, somewhat less visually stunning but still fascinating to geeks, is the discovery by a Japanese team of researchers that certain small snail species have a unique way of achieving geographic dispersal: they get eaten by birds. Now, I’m familiar with the bird vector for seed dispersal, but this is the first I’ve heard of it for snails! The survival rate of the snails isn’t great — around 15% — but it’s enough to get them places they couldn’t go on their own.
One snail in particular helped researchers identify how numerous snails could travel over distances via bird droppings.
“One of the snails fed to the bird gave birth to juveniles just after passing through the gut,” [researcher Shinichiro] Wada told the BBC.
The main factor allowing the snails to survive being eaten is their small size, according to the scientists.
At an average of 2.5mm the micro snails fared much better than larger species in previous studies whose shells were severely damaged when eaten by birds.