Entomology, chemical ecology, evidence-based environmentalism and science in general. I like big bugs and I cannot lie.

Saturday, 24 January 2015

Small lives of the turning year

I've recently been lucky enough to make a friend who feels as passionately about reptiles as I do about insects, who understands the urge to complain about Tumblr photoshops and sympathizes with my complaint that they used THE WRONG TYPE OF MAGGOT in the peach in the film Labyrinth instead of edging slowly away and suddenly becoming very very busy whenever I contact her. We were discussing our favorite creatures and I realised that while there are plenty of insects and other invertebrates whose biology I find fascinating, my personal favourites amongst the ones I encounter in my own garden and landscape are the ones that I strongly associate with a particular time of year.

Male maybug, Melolontha melolontha, image from Wikipedia
Undoubtedly my favorite insect is the Maybug, Melolontha melolontha. Although it's not technically a bug, and technically it's a pest because the larvae eat crop roots (less of an issue now as it was almost wiped out last century) I absolutely adore these big bumbling beetles. They fly about in the afternoon and at dusk, buzzing like little bomber planes, and crash most unaerobatically into anything in their path with a loud thump. The males also have amazing little feathery antennae, the fronds of which increase their surface area to pick up the females' scent, allowing them to locate a mate.

I think my love for them may have developed as a child - there are very few insects in Britain large and docile enough to be picked up and petted, and they'll happily explore your hand on tiny pinscratch claws. (Sadly they were apparently also a favourite with children in less enlightened times, who apparently came up with all sorts of horrible things to do to them.) And last but by no means least, their common name, cockchafer, sounds rather rude!

As their name suggests, maybugs usually start to fly in May. As well as being fascinating in their own right, to me they've always held associations with the beginning of summer, with the arrival of hot lazy days and long golden evenings. I rarely see them now living in London - in my eight years here I've found a single one - and I miss these holiday heralds in the city.

Winged black ants, image by Rebecca Nesbit
For most of the year the Common Black Ant Lasius niger seems fairly unremarkable, but a closer look reveals it to be anything but. For a start they farm aphids, protecting them from predators in order to "milk" them for the honeydew they produce. As every gardener knows, aphids can be pests of plants, sucking the sap and introducing disease. Plant sap is very rich in sugar but has a comparatively low concentration of amino acids, the building blocks of protein, so to get all the protein they need aphids have to take in far more sugar than they could possibly use. They get rid of the excess by excreting a concentrated sugary solution known as honeydew, which to an ant serves as a very convenient sweet energy drink. 

Interestingly, this process is thought to be the reason plants evolved sweet nectar to attract pollinators - having ants guarding their tiny herds benefited the plants too, as ants will eat herbivorous insects as happily as they'll eat aphid predators. Obviously though having their sap sucked by the aphids was a bit of a downside to the arrangement, so plants evolved ways of producing their own sugary secretions, mimicking the aphids to attract the ants. Over time the additional benefit of using highly mobile insects to transport their pollen between plants producing these sugary secretions emerged.

Incidentally this entire system of interactions is utterly fascinating and deserves far more than two paragraph's worth of explanation, but I haven't managed to find a single layperson's introduction to link to so I may have to write my own.

What makes common black ants such a dramatic seasonal indicator though is their mating flights; every year between June and September vast swarms of winged males and immature Queens emerge from their nests to mate and establish new colonies. Although a survey carried out by the Society of Biology revealed that ants did not all mate on a single day across the country as had commonly been supposed, mating flights are coordinated in local areas to produce localised "flying ant days".

When I was a child my family and another used to go on holiday together to the Isle of Wight every summer, driving down with a gaggle of children crammed into the footwells of the car in a way that would be illegal now and probably was then to be honest. We always seemed to manage to arrive in time for the flying ants and while everyone else was picking them out of sandwiches or scraping them off sunscreened limbs, a firm association somehow became cemented in my brain between flying ants and all the good things in life.

Female common green grasshopper, Omocestus viridulus,
image from Wikipedia
I know I'm cheating a little here by not picking a single species, but others insect I associate very strongly with high summer are the crickets and grasshoppers (there's a good explanation of the difference here. Grasshoppers are active during the day, unlike crickets which tend to be active at dusk, and they are most active in warm weather. As warm weather is also when I'm most likely to be found sprawling on the grass, in summer when the sun has baked the grass roots almost to straw is the time when we're most likely to bump into each other and nothing says "camping holiday" quite like having a grasshopper suddenly materialise on the page of the book you're reading only to spring away again at the slightest shifting of your fingers. And there can be few people for whom their trilling song doesn't evoke lazy summer days.

Female Araneus diadematus. Image from Wikipedia.

As summer comes to an end and the autumn evenings draw in, misty and mysterious, Britain's spiders really come into their own, festooning the garden with their silken webs. The most skilful weaver is the garden spider, Araneus diadematus.

The spiders themselves are as beautiful as their webs, with a wide variety of colours from restrained neutral tones of taupe and dove grey to rich deep chocolate and mahogany or sunny gold, and when the females are gravid their abdomens are large enough to notice the cross-shaped markings and really appreciate the intricate stippled patterns. There are some gorgeous pictures showing various different colourations here, or I would really recommend doing a Google image search for all the beautiful pictures I can't share because they're not public domain.

Special mention too should be given to the various species of house spiders which wander indoors in autumn in search of a mate and instead tend to meet a swift and crunchy end at the paws of the cat, who unfortunately views most invertebrates as entertaining snacks. The Natural History Museum produces a handy guide to the most common species likely to be found indoors which is available here (pdf).

Compost, image from Wikipedia. Okay I'm cheating a bit with this one but I defy anyone to find an artistic, Creative Commons licensed image of a worm.
Invertebrate life is less apparent in winter, when most cold-blooded creatures burrow down into the ground or huddle in cracks and crevices to wait for the return of the warm days. One species I still encounter on a weekly basis though is the horde of composting worms (Eisenia spp) that live in my garden wormery (pdf), eating through our kitchen waste and producing compost. Although they slow down in winter the wormery is insulated and the decay of compost making generates its own heat so they keep working all year round. 

Worms may not be the most charismatic creatures in the garden it's true, but I find it amazing that something that is essentially a stripy tube can bring about such a miraculous transmutation, turning mouldering kitchen leftovers into dark, crumbly compost that you'll want to sniff deeply at and run through your fingers when it's warmed by the springtime sun. Their distant cousins the earthworms do this vital recycling job on a much larger scale in the garden soil, keeping nutrients flowing ceaselessly through the ecosystem. I find the whole concept of nutrient cycles deeply comforting on an almost spiritual level as a reminder that we're all connected, humans and soil and microorganisms and vegetables, we're all made of the same things on a fundamental level, and we have worms to thank for the fact that these fundamental building blocks are constantly in motion, in flux through a greater whole.

Buff-tailed bumblebee,  Bombus terrestris, image from Wikimedia Commons
Some of the first insects to reappear in spring  are the bumblebees. There are numerous common species in Britain, which can be distinguished by their markings.  Unlike honeybees, only the queens of these fuzzy, large-bodied bee species survive the winter, by hibernating underground. In spring she must first build her own nest and forage for nectar and pollen herself before she can start creating her brood of minions.

All cold-blooded creatures are sluggish on chilly early spring mornings and struggle to get moving (I can sympathise) but bumblebees are able to decouple their flight muscles from their wings and use them to generate body heat which allows them to fly earlier in the year than most other insects, as this thermal video shows.

Large bee-fly Bombylius major, image from Wikimedia Commons.
Another spring arrival often confused with bumblebees are the various species of bee-flies. In spite of their appearance these are actually diptera not bees, true two-winged flies like houseflies or greenbottles. Their appearance mimics that of bees to deter predators, and like bees the adults feed on nectar using their long proboscis to visit early spring flowers like primroses and violets. A lot of people who've contacted me to identify them find this proboscis quite alarming, but it's for flowers only and they don't harm humans.  Bees themselves are a different matter though - bee-flies are parasites of solitary bees, shooting their eggs into bees' tunnels where the vampire-like larve parasities the young bees. Which just goes to show you can't trust anything cute and fluffy.

The large bee-fly incidentally has the glorious binomial name of Bombylius major, which always makes me think of a rather pompous and portly retired military gentleman.

13th century depiction of the turning of the seasons from
Liber Divinorum Operum by Hildegard von Bingen
I have been through some difficult times in the past, and through them I took great comfort from the changing of the seasons, from the knowledge that nothing was permanent and that winter would inevitably be followed by spring. It was reassuring to know that whatever happened to me, whatever struggles I may have had or mistakes I made in my personal life, the Earth would continue on its path around the sun. The days would lengthen and shorten in their predictable cycles, sap would rise and fall, living things would wake and rise and feed and breed and sleep just as they had always done and would always do.  The constant novelty of the turning year gave me reasons to hope too, the knowledge that if I just held on a little longer I would see snowdrops and daffodils and hawthorn blossom, I would taste strawberries warm from the sun and English apples and little oranges smelling of warmth and spice and Christmas, I would see bees on lavender and peacock butterflies and cobwebs like jeweled lace.

The tiny invertebrate lives beneath our feet are so often overlooked in the when we appreciate the endless variety of the circling year. I hope this post will encourage some people to look for them, and note them, and smile.

Monday, 5 January 2015

Natural History: not just for boys!

Hat tip to Marianne for bringing this to my attention.

As a child I was lucky enough to grow up close enough to London's Natural History Museum to be regularly handed a Sainsburys carrier bag full of Capri Sun and small plastic cheeses, packed on a school bus and taken on trips to it. Once the car sickness and the lingering suspicion that Gareth had called me a rude word (even if I wasn't quite sure what it meant) had worn off it was always a thrilling experience.  Imagine if you will being a tiny child who not only thinks animals are THE BEST THING EVER but is slightly light headed from having been sick over Lara's pencil case on the journey in, walking into a building that looks like a fabulous fairytale castle to be greeted by a Diplodocus skeleton. I remember being awestruck by how thick the leg bones were, the sheer mass of these creatures I'd only seen in picture books suddenly becoming tangible, the blackened bones hinting at an age I can barely comprehend even now. It was magic.

Image from http://www.nhm.ac.uk/

It was also, as I was vaguely aware of even then, something that was supposed to be for boys. The books I'd first seen dinosaurs in, the Top Trumps dinosaur cards I played with, even my first microscope, were meant to be for my brother but were gradually appropriated, either stealthily or ocassionally with extreme violence.  But that was over two decades ago, and nowadays little girls are encouraged to have an interest in science and natural history right?

Unfortunately not.

The Natural History Museum has recently licensed Marks And Spencer to produce a range of children's clothes with its images of dinosaurs and insects on. They're pretty cool; I won't lie, if this T-shirt came in adult sizes I'd want one even if very few of the "bugs" on there are true bugs (I'm half-pedant, on my father's side).

Image from M&S 
Unfortunately I'm not just excluded from buying this on grounds of my age and theoretical maturity. The Natural History Museum range on the M&S website is marketed exclusively at boys. While there is of course nothing stopping anyone buying a boys' shirt for a girl or vice versa, segregating these t-shirts into gender categories not only means people browsing the M&S website for girls' clothes won't see them but also reinforces the subliminal message that dinosaurs and insects, that cool things that are fierce and messy, are for boys and not girls.

And quite franlkly that's just sad, that there's a whole fascinating area of the natural world that girls are slowly and steadily given the message isn't for them to experence. I've done a few public engagement events introducing children to insects, and one of the saddest realisations I've had doing this has been that there's not much difference in interest between boys and girls among primary school kids, but by secondary school the girls have learned that they're supposed to shriek and be disgusted and back away while the boys are still happy to investigate.

Image from Let Clothes Be Clothes

I'm not the only one annoyed about this. Let Clothes Be Clothes (the sister campaign of Let Toys Be Toys) has launched a petition to both M&S and the Natural History Museum, urging them to make this range available to children of all genders which I'd urge everyone reading this to sign. And to those who would argue that this is just an issue of "political correctness gone mad" and it's children themselves who exhibit these preferences, remember that it was a seven-year-old girl herself whose protests convinced the publishers of "The Baddest Book of Bugs for Boys" to change the title.

After all, probably the most famous dinosaur kids will encounter is herself female.

Friday, 21 March 2014

So much science communication fail today

A helpful guide for anyone looking to communicate research or research priorities:

"Sex" refers to the biological and physiological characteristics that define men and women.
"Gender" refers to the socially constructed roles, behaviours, activities, and attributes that a given society considers appropriate for men and women.
Seriously people, your subject may be fruit flies or endangered insects or coconuts, but you don't get to forget that your audience are people.

Monday, 3 March 2014

Ticked off at the news

Today I heard the sad news that the Borreliosis and Associated Diseases Awareness UK charity is ceasing operation as a charity due to lack of funds. We in the UK are comparatively lucky in vector-borne disease stakes, able to enjoy the great outdoors without too much concern about being bitten by something that'll give us something 'orrible, but one that we do have to deal with is Lyme disease which along and its relatives, transmitted by the bites of ticks which contrary to popular belief are arachnids not insects. Lyme disease can be debilitating (as is shown by my friend's blog about living with it) and it is still often initially not correctly diagnosed, which is why the campaigning work of BADA UK has been so vital and their closure is such a tragic loss particularly now that the incidence of Lyme disease appears to be on the increase.

This campaigning was so important because there is a lot of misinformation out there about ticks and the diseases they transmit, and not just this sort of thing:

I spend more time on Pinterest than I probably should and I've encountered some quite horrifying pins describing this one weird trick some [nurse/mom/other trustworthy-sounding person] has discovered to remove ticks. Needless to say the vast majority of them are a very bad idea, which is a serious problem as incorrect removal can increase chances of disease transmission. Fortunately some colleagues of mine recently published a review paper on best practice:

Avoiding ticks


Encouragingly a randomised controlled trial showed that infections were less common in people who received education about ticks. Congratulations, by reading this post you've just joined the lucky group! The best way of preventing disease transmission is not to get bitten in the first place. Cover up: wear  trousers and tuck them into you socks - I know it looks daft but you can always pretend you're Tintin.  And if you're feeling really fancy you can even get clothes impregnated with the insecticide permethrin which has bee shown to be effective in reducing the incidence of tick bites, although it does need retreating frequently to remain effective.

Everyone's favourite racist, cultural imperialist boy reporter.
The next line of defense is to use a repellant, a substance that beasties find unpleasant smelling that you can rub on your skin to put them off their lunch. Trans-p-methane-3,8-diol (PMD), or lemon eucalyptus oil to its friends, has been shown to be highly repellent toward ticks and in laboratory studies was still providing some protection 48 hours later. By contrast there is little evidence for the effectiveness of DEET against ticks, and what evidence there is seems to suggest it only has a short-term effect. (It should be noted that this is different from the situation for mosquitoes, against which DEET offers better protection).

Tick removal

The faster you can remove a tick, the less chance it will have to get bacteria into your bloodstream. Check yourself every few hours for ticks, and - waggles eyebrows suggestively -see if you can find a tick buddy to check the areas you can't see yourself (or more boringly use a mirror).

Tick removal is the step that seems to have produced the most dangerous home remedies.  Trying to suffocate the ticks with petroleum jelly, nail polish or rubbing alcohol is likely to be ineffective as ticks respire very slowly so can keep feeding without air long enough to infect you, and if you do manage to damage or kill a tick by one of these methods or using a lighted match there's a danger that parts of it will be left in your skin, posing an infection risk. (Needless to say combining rubbing alcohol and a lighted match would be a terrible idea.) BADA has an excellent series of photographs demonstrating correct removal on their very informative website, which will remain active until December 2015: using tweezers, and using a specialist removal tool. At present the evidence in humans suggests that the safest method of tick removal in humans is to use fine-tipped tweezers - evidence for the effectiveness of the tick removal tool only comes from veterinary medicine.  However, if you're not comfortable with tweezers the removal tool is probably a better bet than any of the other methods out there. The TickTwister tool is available to buy here.

If you've been bitten


Although the characteristic bull's eye rash is probably the best known Lyme disease symptom, it only appears in around 60% of patients.  Other symptoms include:
  • unexplained headaches and neck stiffness, 
  • flu-like symptoms,
  • facial palsy, 
  • arthralgia
  • heart palpitations, 
  • dizziness 
If you experience any of these within a few weeks of being bitten by a tick, or of being somewhere you know ticks are present even if you didn't notice a bite, you should see a doctor.


Bull's eye rash, from BADA
Your GP should be able to carry out further tests, and prescribe a course of prophylactic antibiotics if necessary.

So get out there and enjoy the countryside, but respect it too: even here in the UK we have disease vectors that could make you very sick if you give them a chance!

Tuesday, 21 January 2014

Go hug a bug!

I recently attended an event organised by a group of open-minded, environmentally conscious people. I realise that makes it sound like a sex party but I assure you it wasn't, I'm being deliberately vague because this isn't a complaint about a specific person or group of people, but a wider problem about our attitude to insects. At one point in the evening I got chatting to a bloke who was clearly a very intelligent person (this is sounding dodgier and dodgier) and evidently passionate about environmental issues. We discussed how the loss of hedgerows was reducing songbird habitats, and whether it was possible to compensate to some degree by growing hedgerow shrubs in gardens.  We discussed how little exposure city children got to nature, and how far it was possible to care about the environment if you weren't personally familiar with it. He told me he'd been working on a project to reintroduce willow coppice onto some neglected land that day and that he'd found a cluster of insects on one of the trees that he'd never seen before, which from his description sounded like large willow aphids.

Large willow aphids, winged and wingless forms.  Picture from the Sussex Wildlife Trust.

Every entomologist loves an easily identified insect, and as a description "it had three triangular spikes on its back" (especially if it was on willow!) is a great deal easier to work with than "it was small and black".  Although the large willow aphid is one of Britain's largest and most distinctive aphids its lifecycle is still surprisingly mysterious - no one has ever found a male (maybe it does without them) and no one knows where they disappear to for almost half the year. So I told him this, and he in turn told me that he'd killed them, and I asked "WHY?" and did a fairly decent impression of Jenna Marbles.

He at least looked a bit embarrassed about it, but told me that he always killed insects he didn't recognise because he lived in London, near Heathrow, and assumed that anything that looked odd (for example something with three horns on its back!) must be a dangerous invasive species that had come in on a plane or with some imports.  He explained that he'd killed loads of false widow spiders - even if all the spiders he killed were in fact false widows, which I think is unlikely, they're not nearly as dangerous as the media makes them out to be. Needless to say, hearing these attitudes from a smart, committed environmentalist made for a very sad entomologist.

I always find it rather sad that the reaction of so many people, including informed environmentalists who should probably know better, to arthropods is fear and disgust.  Not only are these creatures fascinating and, to my eyes at least, beautiful in their intricacy, they are also a vital lynchpin of the ecosystems that support all life on this planet including ourselves and (while this may seem an odd sentiment from someone who studies pest control) the sixty percent of invertebrate species that are declining are more vital for us to conserve than cuddly, charismatic mammals like tigers or gorillas could ever be.
If we and the rest of the back-boned animals were to disappear overnight, the rest of the world would get on pretty well. But if the invertebrates were to disappear, the world's ecosystems would collapse.’ Sir David Attenborough - See more at: http://www.buglife.org.uk/#sthash.xrwYmpio.dpuf
"If we and the rest of the back-boned animals were to disappear overnight, the rest of the world would get on pretty well.  But if the invertebrates were to disappear, the world's ecosystems would collapse" - Sir David Attenborough.

Although it's often assumed that we're hardwired to fear arthropods there is surprisingly little hard evidence for this theory, and it is by no means a universal human experience outside the west - insect collection is something of a Japanese national obsession, and insects are routinely included in peoples' diets throughout the world (very large pdf) as a vital source of nutrients which sadly is increasingly being abandoned due to the adoption of Western prejudices. (The fact that we entomologists don't feel the same way is also awkward for this theory as it rather suggests that we're the next stage of human evolution, and much as I love you all guys if that's the case we're probably doomed as a species.  Or at the very least about to become a great deal hairier).

Sadly I think much of the problem lies with our culture - what we're taught at school and what we see and read in the media.  So much reporting on arthropods seems to be about DANGEROUS INVASIVE SPECIES THAT WILL KILL YOU DEAD! or at least ruin your hairdo that it's hardly surprising that many people view insects as invasive aliens that will lay eggs in your eyeballs then kill you to death.  Even non-scaremongering stories are often negative - can you imagine a famous, popular columnist writing about mammals in this way for example?

Image from Simon Leather's post on the importance of communicating through social media for entomologists.
So what can we do about it?  In the case of the chap in the first paragraph I must confess I got his details through Facebook and sent him a copy of Chinery, and am expecting the restraining order any day now.  But for the general public the only solution is more engagement and education.  There is always a temptation, which I know I've fallen prey to at times, to focus on the horrifying or grotesque in the insect world as a way of grabbing attention.  But I'll try to avoid that in future - there's already plenty of that in the media so in the interests of balance I'll try to focus on what incredible, amazing creatures insects are and how they really don't deserve to be squashed on sight.

Insects need love too.
If we and the rest of the back-boned animals were to disappear overnight, the rest of the world would get on pretty well. But if the invertebrates were to disappear, the world's ecosystems would collapse.’ Sir David Attenborough - See more at: http://www.buglife.org.uk/#sthash.xrwYmpio.dpuf

Wednesday, 25 December 2013

Happy Christmas!

Here's one of the oldest known illustrations of a turkey, from Konrad Gesner’s Vogelbuch, 1557.

From Kansas City's Linda Hall Library.

Saturday, 16 November 2013

Praying mantis by Becca Stadtlander

Through the magic of Pinterest I've discovered this artist who does lovely nature illustrations, you can find her Etsy shop here.  To me this picture perfectly illustrates this wonderful description Gerald Durrell wrote of the mantids he encountered as a child in Corfu:

"Among the myrtles the mantids moved, lightly, carefully, swaying slightly, the quintessence of evil. They were lank and green, with chinless faces and monstrous globular eyes, frosty gold, with an expression of intense, predatory madness in them. The crooked arms, with their fringes of sharp teeth, would be raised in mock supplication to the insect world, so humble, so fervent, trembling slightly when a butterfly flew too close."
 Apologies for the lack of activity here lately folks, normal service will resume once I submit my thesis.