Musings

Friday, January 09, 2015

Buff-tailed bumblebee

In order to make up from some rather lazy posting of organisms from far flung times, this one's right up to date. Amazingly this beauty bashed into my kitchen window this morning as I was re-fuelling the wine rack. 
There was a slight delay as the penny dropped: what on earth was a bumblebee doing out at this time of the year and in weather like this. (The sunny spell was a freak event in a long period of either cold or wild and milder weather. It is now wild and mild outside with gale force winds.)
I am no expert on bumblebees but I think this is Bombus terrestris. The only concern is that the stripe on the thorax is a little orangey. I posted it on iSpot hoping for confirmation, but none as yet.

There's something endearing about bumblebees that spiders and flies just don't have. I think it's their ridiculous proportions and their hairy/furry appearance. Denuded of hair and seen in their chitinous wherewithal they'd create a quite different reaction. 

They used to be called humble-bees, quite commonly, up until around the first world war, as well as bumblebees. Both are very old names, with the former recorded in the fifteenth century and the latter in the sixteenth. Then, for no discernible reason, the use of humble-bee just gradually tailed off. Since the second world war only bumblebee has been used as the common moniker. Weird.

Humble-bees are in the phylum Arthropoda, the class Insecta and the order Hymenoptera. It is one of the largest orders, with over 150,000 species of ant, bee, wasp and sawfly described. The name refers to their membrane wings (from the Greek). The family is the Apidae, which basically contains all the bee-like, waspy type creatures. Important pollinators all (when not being discombobulated by neonicotinoids and the like!). 

The other notable thing about humble-bees is that Uncle Charles (Darwin) cited them in a discussion about the interconnectedness of species. To paraphrase: humble-bees seem to be the only pollinators for some plants; the number of humble-bees is inversely proportional to the number of field mice (which predate the nests); the number of mice is inversely proportional to the number of cats; there are more cats near human habitations; therefore the keeping of cats by humans influences the success of some flower species. A correspondent of his, Mr Newman, had observed more humble-bee nests near to villages and towns and this provoked the ideas. The term 'ecology' wasn't being used at the time.

Another curious thing about humbe-bees is that their eponymous buzzing comes not from the wings beating the air, but from the noise of their flight muscles. The wings beat at around 200 times per second, which is faster than a nerve could repeatedly fire. The muscles actually vibrate after each nerve stimulus, which is not only physiologically necessary, but also much more energy efficient. They can de-couple their muscles from their wings and will use this to bring their body temperatures 'up to steam' before take-off if the ambient temperature is low. 

No comments: