One of my favorite spiders, when I was young, was Tegenaria, Eratigna, I mean Malthonica, or maybe just cellar spiders. The taxonomy of these spiders is another one yet to be finished. Large, dark brown spiders living in huge funnel webs. In basements, or outside under wood or rubbish, they were easy to find and sometimes came in large numbers. And the extremely leggy males caused some freaky moments when they were looking for a female and got caught in a tub or sink… I used to call them T. domestica, but then I read about T. atrica (in the genus Eratigena now), and then I continued reading and gave up because it seems there are a hundred species, and some were transferred to another genus (Malthonica), and new species were described. And somehow they all look similar. Again I have to admit that a save ID is not possible.
What’s their point about biofuel? Of course, they don’t care about fossil energy sources and green alternatives. But we know that animals, as well as humans, communicate via chemical signals (hormones!). So the question was, why are these spiders sometimes peaceful, and other times they cannot stand each other? Or how does a mother spider recognize her babies? In some studies substances, that are very similar to biofuel (methyl esters of fatty acids), were found to be used for communication. To be more precise, it leads to aggressive behavior between them. Additionally, alkanes, which are in fossil fuels, are part of the communication as well. But these substances signal pro-socializing. Looks like our living fossils are not yet going green!
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