Happy Halloween!

Things that go bump in the night

As the nights grows longer and days grow colder, people across the world usher in the winter solstice with gatherings twisted in myth, superstition and celebration. Halloween, heralded as the night when the boundaries between the world of the dead and the world of living become blurred has evolved over time, but grim and ghoulish creatures remain a central theme.

The Spider, a quintessential Halloween creature, with its alien form and in some species, deadly capabilities, human misunderstanding of these interesting species has had a long history. Meet Nephilia komaci, the largest orb weaving spider known to science and a bit of a biological enigma. This rare species of orb-weaving spiders are native to South Africa and Madagascar. The extreme differences in size between the sexes, makes them evolutionarily interesting. Males can reach a modest 2.5cm where as females can reach a frightful 12cm leg span. Researchers suggest the female developed such a large body size to increase fertility (ablity to lay more eggs) whilst being a huge deterrent to any smaller predators that might happen to pass by. The Nephilia komaci web weaving skills are some of the best with some webs reaching one meter wide!

‘They mostly come at night, mostly...’ But not always, Bats aren’t quite the blood sucking children of the night as you might think. These complex creatures are some of the most interesting mammals on the planet. The notorious Vampire bat has long had links to Halloween with their nocturnal lifestyle and blood sucking behaviour but let’s separate the fact from fiction. There are only 3 species out of over 1000 Bat species that feed solely on blood. It is true that they are nocturnal, but not only do they use caves for shelter, various species throughout South America have been known to make use of a wide variety of locations from hollowed trees to abandoned mine shafts. Although they indeed feed on the blood of mammals it is not sucked, but in fact the skin is pierced and the blood lapped from the wound. With an average of 2-4 tsp being consumed each night this is hardly a feed of vampiric proportions.  One of the less well known and incredibly endearing qualities of the Vampire bat is its altruistic behaviour.  These bats are vulnerable to starvation if they do not find a blood meal more than two nights in a row. It has been shown that fellow cave dwellers will regurgitate a blood meal to insure the survival of the receiver at a small cost to their own fitness. The expectation is that the favour will be returned in the future, when the other bat may need a meal. Once you know this, they seem rather friendly and considerate little creatures quite apart from the tales of Dracula!