It’s been a little quiet around here so today you’re getting two posts to make up for it. This afternoon we’re going to have a guest post by Plymouth Museum’s very own Jan Freedman but first let’s talk about bugs:
London’s Natural History Museum houses an impressive natural history collection. It has millions of specimens ranging from amoebae to blue whales. For Dr. Erica McAlister, an entomology specialist at the museum, the most important part of the collection are flies. Many of us relate to flies as a nuisance that needs to be swatted away from our sandwiches but, to Erica, they represent an amazing resource of information. Last month Erica agreed to come and talk to the good people of PubSci about her research.
There are two primary frontiers of insect research: new areas of investigation; and cleaning up the mess Walker left behind. We’re going to talk more about the new areas but I’m sure Erica would be happy to tell you about Walker’s legacy if you’re not already familiar with it.
New areas include a recent trip to the Ethiopian church forests. This is an interesting phenomenon – deforestation for farming has decimated the Ethiopian forests but, due to their reverence for the church buildings, the forests have been left unscathed in a radius around them. This may be the last hope for many of Ethiopa’s native species. Flies are a major contributor to pollination – three of the six top UK pollinators are flies. What Erica wanted to know was whether the speciation at the edges differed from the core. She went out there and, despite some regional obstacles such as children stealing pan traps, managed to recover a huge amount of data – which has since been published.
Another major area of investigation has been identifying fly larvae: we may have over 100 000 described species of fly but we only know 4% of their larvae. The importance of this cannot be stressed strongly enough: if you cannot tell apart a disease carrier from a pollinator you may be shooting yourself in the foot however you tackle them. Furthermore their presence at the developmental stages of a crime scene could drastically alter your prediction of how long ago the crime took place if you do not get the species right.
Flies are used as an arctic bio-indicator of climate change because certain species of chironomids (non-biting midges) are ctenothermic and can only exist in very specific temperature ranges. There now exists a ‘chironomid thermometer’ due to this phenomenon.
Suitcase ecology is another area of crime scene investigation. It was once believed that the age of a body couldn’t be as accurately determined if the body was stowed away in a suitcase because flies cannot get into and out of it. Further study has revealed a pattern of egg-laying on the zip, through which the larvae may pass when they hatch. This now gives us a better picture of the circumstances of the murder than ever before.
There are lots of fly behaviours that touch upon our daily lives in ways we don’t even appreciate and understanding these is essential to our continued way of life. For example the very fact that we have chocolate is wholly due to fly pollination. Without them, we wouldn’t have it. Furthermore we can use flies as a source of chemical research – fly venoms used for biological control, for example. We need them to tell us whether the climate is changing and to help us catch murderers but, more importantly, we need people like Erica who can make sense of their behaviour and present it in a way that makes us forget our instinctive “ugh, flies” reaction. There aren’t many people who would be prepared to trawl through cow pats and fetid carcasses in the name of science but somebody has to. When someone steps forward and shows enthusiasm for this we should wholeheartedly encourage it.
PubSci is a pet project of NatSCA Chair Paolo Viscardi. If you’re in London tomorrow evening I highly recommend you come along. We will be talking about the history of natural history collecting and trade with Elle Larsson, University of London postgrad. I am sure it will be terrific.