Animal of the Week -- November 10, 2008

"The sea has its large rivers like the continents. They are special currents known by their temperature and their colour. The most remarkable of these is known by the name of the Gulf Stream. Science has decided on the globe the direction of five principal currents: one in the North Atlantic, a second in the South, a third in the North Pacific, a fourth in the South, and a fifth in the southern Indian Ocean. It is even probable that a sixth current existed at one time or another in the northern Indian Ocean, when the Caspian and Aral seas formed but one vast sheet of water."

So mused Professor Aronnax aboard Captain Nemo's Nautilus in Jules Verne's Twenty Thousand Leagues Under the Sea.

It is such rivers that helped this week's animal, Megaleledone setebos become the forebear of many species of deep sea octopus. A study from the Census of Marine Life show that this unassuming octopus of shallow Antarctic waters is the likely forebear for many diverse species of deep-sea octopuses. Researchers believe that ocean currents, such as Professor Aronnax's rivers, carried larvae from the shallow Antarctic waters to the deep sea where, in isolation, and under the new selective pressure (quite literally in the deep oceans) they diverged into separate species. The idea that a living species is the ancestor of others is mighty exciting. It's like stumbling across the last common ancestor of chimps and humans alive [Have you been to Norfolk lately? -- Ed].

The development of these rivers, or thermohaline expressways, is associated with expansion of the ice caps, as fresh water is sequestered in ice caps, concentrated cold salt water sinks helping to create the currents that then flow into the deep oceans -- carrying species from shallower waters with them. Successive periods of activity of these currents related to global warming and cooling create successive waves of immigration to deep sea areas leading to a greater diversity.

As cold waters sink away from the poles, warm waters are pushed and drawn towards them, hence the Gulf Stream keeps the UK and other parts of northwestern Europe, which should be as cold as Canada, ice free. As human-generated global warming melts the ice caps, the Gulf Stream may be disrupted, actually causing temporary cooling of the British Isles and Norway... before we all fry, starve, and die in wars over access to water and Ambre Solaire.

Happy days

Animal of the Week -- October 6, 2008

As I am sure that you are all aware, in the UK Red Squirrel Week started on October 4. And during this period we are all asked keep in mind the much beleagured European Red Squirrel. And so, in honour of Red Squirrel Week, although totally without ties or affiliation, this week's animal is Scuirus vulgaris.

It's may not be a coincidence that almost three years ago to the day animal of the week recognised the crazy crack squirrels of Lambeth— which, judging by the erratic behaviour of one that leapt onto my friend Talha while walking through Elephant and Castle the other week, have now spread to Southwark. But those were the eastern grey squirrels, invaders from the USA that have outcompeted the native red squirrel and spread diseases that have pushed our reds to the fringes of their former range. During Red Squirrel Week, we are asked to report sightings of red squirrels, particularly any ill looking ones that might have caught squirrel pox from their grey usurpers to help gain a better picture of the extent of the species and the extent of the disease. Your best chances of spotting reds in the UK are around Poole Harbour, the Isle of Wight, Anglesey, Cumbria, Northumberland and Scotland.

Outside the UK the red squirrel is still quite common, grey squirrels having failed to make it to continental Europe (although in Piedmont, Italy, a population of greys has become established and is squeezing the reds from their former range). Greys outcompete reds because they are larger and able to exploit more foodstuffs than the reds -- such as acorns, which give the native reds bellyache.

Confusingly, grey squirrels can appear quite red, and red squirrels come in a variety for shades, from auburn to black, from ginger to, er, grey. If you see a red-tinted squirrel throughout most of the UK, not in the areas above, it is probably a grey squirrel and certainly not, as has been suggested to me before, the result of cross-breeding between the two species. If you see a red squirrel in North America, it will be an unrelated North American red squirrel. The best way to spot a European red is to look for the ear tufts, these little fluffies have prominent squirrel nutkin tufts; whereas greys and other reds do not.

In norse mythology Ratatoskr is a squirrel who runs up and down the World Tree (from which the nine planes of existences hang), spreading news, rumours, and gossip, and ferrying isults between the eagle in Asgard atop the highest branches and the dragon curled up in Hel beneath its roots.

Many thanks,

Peter Hayward
Head Keeper
Animal of the Week

Animal of the Week -- September 15, 2008

Wherever you look in the news this week, one thing is for sure: ants are where it's at.

First off the news that a blind, subterranean species of ant with huge mandibles discovered in the Amazon a couple of years ago represents a whole new ant subfamily, provides unique insights into the origins of ants. Ants arose from wasps, but perhaps all living ants are descended from ancestors that once lived underground permanently. So weird is this ant that it's name, Martialis heureka, suggests that it might have come from the planet Mars (Martialis). The huereka presumably harking back to the Archimedean cry of scientific enlightenment. Taxonomists are crazy!

By contrast, this week's actual animal of the week is an example of totally uninspired taxonomy: Formica rufibarbis. Now, you may well think that this is a cocktail of downers mixed on a 1970s composite plastic worksurface, but it's actually the red (rufi) barbed (barbis) ant (Formica -- the most familiar ant genus). The naming of this ant is totally lazy, it is indeed, a bit red and what's more it has little barbs on its back... and it's an ant. Taxonomists are, most of the time, boring! But for all that laziness, there is currently a great effort to save this ant from extinction in the UK.

Although widely distributed, the red-barbed ant is never common within it's range from Portugal to Siberia, and in the UK, its highly picky living requirements mean that it can only be found on St Martin's in the Scilly Isles (and why not, that's nice enough) and Chobham in Surrey -- presumably moved there for the schools. However, the mainland population has declined so much that only one colony remained, and due to a reproductive quirk of the species that only produced females. Now the Zoological Society of London and partners are reintroducing captive bred nests, some of males, some of females, onto heathland in Surrey.

The ants have fared poorly in the UK due to habitat destruction. To ease the tranisition for the captive bred ants great effort has gone, not only to preparing suitable habitat for them, but into trying to remove one of their main enemies in the natural world -- Formica sanguinea. This latter ant steels larvae from other colonies and raises them (ahhhhh, that sounds alright -- sort of like Madonna or Angelina Jolie) but then makes the matured ants do all their work for them! As the red barbed ants are released on Chobham downs on Monday, I wish them all the success in the world and salute the work of the tireless souls who work to ensure their continued presence on this sceptered isle.

Animal of the Week -- August 18, 2008

Look! What's that over there in the bushes? Pass the me the binoculars will you. OH MY GOD! It's a lesser spotter Animal of the week.

It's all been crazy talk of bigfoot and chupacabras from the states recently -- but predictably they turn out to be a monkey suit in a block of ice and a manky old dog. So, I am going for something totally unsensationalist.

If you were to ask me what my favourite animal was, I'd be hard pushed to come up with an answer -- I mean there are bloody loads of them. Would it be a majestic lion, or a honey-making bee? The vanishingly rare Vancouver Island Marmot, perhaps? Maybe it's a fluffy viscacha, or the parasitic carandiru that swims up people in the Amazon? Or a barnacle that replaces the body of a crab in while the crab is alive? There is so much fluffy-cute, crazy-arsed weird-shizzle going down in kingdom animalia that really I wouldn't know where to start picking a favourite. But then, maybe, just maybe...

While visiting my ma's recently to catsit while she took a holiday, I was gazing out over the patio when I noticed a commotion in the hedgerow -- 20 or so tiny black dots fizzing around from tree to tree, and I suddenly felt full of joy and realised that nothing warms the cockles of my heart as much as a flock of this week's Animal Aegithalos caudatus (long-tailed tits).

These birds are small about 8 cm long, more than half of which is their tail, they are fairly common throughout Europe and western Asia, and they are not endangered, particularly useful to people, or really in any way remarkable. But there is something about these tiny balls of feathery fluff, as they swarm over individual bushes, their black and white bodies flecked with pink bars on their wing, swapping places, following one another, emitting shrill, almost supersonic, three-note chirping calls, picking off small insects from among the bark and leaves. They are like tiny clowns -- but nice clowns, not fright-wigged, red-lipped, custard-in-the-pants, It clowns. Just following the path of a flock of these little tits down a hedgerow, or across a scrubby heath, or through a stand of trees in an inner city park or cemetery is one of life's great joys.

Also, now as we head into late summer, while you are out blackberrying, if you spot in some dense scrub a small round ball of moss, feathers, and lint stuck together with spiderwebs, you have probably found a long-tailed tits nest, incredibly well camouflaged and hidden, they are not uncommon but they are hard to spot.

So keep your eyes and ears peeled, if you see little round birds with long tails bubbling through a hedge, singing a high pitched song, take a few minutes to enjoy these charming little tits.

Animal of the Week -- July 28, 2008

I suppose that the name "Animal of the Week" doesn't necessarily imply there has to be an animal every week, just that when there is one, that's the animal of that week. And a week is pretty much undefined, there's the strict Monday to Sunday concept, but then any group of seven adjacent days is also a week. So the animal of this week is Ptilocercus lowii (pen-tail tree shrew).

Now, as someone who is not averse to the odd jar myself -- I was impressed to read in the newspapers earlier this week that these diminutive distant relatives also actively seek out alcohol and drink enough to be drunk 36% of the time. In the forests of Thailand and Malaysia they are to be found supping on fermented nectar from the flowers of bertam palms. However, the reasearch, published in the Proceedings of the National Academy of Sciences USA shows that rather than get drunk, the alcohol is disposed of in the tree shrews' hair as a chemical that is also found in the hair of humans with chronic alcoholism [those that have hair, eh? -- Ed][Shut it you! And who the hell is this ed anyway? -- PH].

Thought to be similar to the last common ancestor of all primates that lived about 55 million years ago, pen tail tree shrews, named for their mostly naked tail fringed with lateral hairs like a quill on the last third, are the only nocturnal tree shrews. If disturbed during the day they are sluggish, responding by rolling on their back, hissing, urinating, and defecating in defence. I think the researchers who say these critters aren't affected by the booze had better think again.

Much has been made of their prodigious alcohol consumption -- but it turns out the nectar of the bertam palm is only 0.5–3.8% alcohol. It's hardly a bottle of tanqueray now is it? I'll let them off though, at only 50g, they're definitely not lightweights

Animal of the Week -- July 7, 2008

After the most recent animal of the week a goodly number of folk contacted me to let me know that they had recently seen silverfish, a surprisingly small number, or zero, of these correspondents felt as well disposed towards the graceful little darlings as I do -- most feeling repulsion, disgust, or even fear.

I suspect that this week's animal might also divide opinion, but I'll probably have one or two more people on my side, as this week's animal is the scourge of one of the biggest causes of animosity among neighbours in modern day towns, villages, and suburbs. Although they are a gift to the producers of TV shows about societal conflict in the form of boundary disputes, a great many people abhor leyland cyprus arbors; but across the land, there is a new friend to those living in the shadow of the much loathed conifers -- Cinara cupressi (cypress aphid).

Probably originating in southeastern Europe, these grey 2–3 mm aphids are now found on every continent but Antarctica where it is warm enough for them to breed. In the UK their numbers are largely kept in check as cold winters kill off large numbers of them. However, due to global warming caused by people reading ridiculous almost-weekly emails about animals and the like, last winter the temperature in the southeast was practically tropical throughout. As a consequence these little beasties survived in large numbers. A couple of months ago they began their onslaught, sucking the sap from leylandii hedges up and down the country. Now, the damaged plants are turning brown, whole section and some complete plants dying.

Obviously, this is pestilent behaviour by the aphids, but the hedges are stupid, so good on them I say. Except for those attacking mazes, the only acceptable use for a leylandii. I love a maze, even though I know how to do them and have to resist the temptation to cheat.

Throughout the summer the aphids reproduce parthenogenetically -- ie, the females spew out identical miniatures of themselves without the involvement of any male aphids. A female may contain another female that is already pregnant with the first female's granddaughter, like an entomological russian doll. As winter approaches males are produced by withholding one of the sex chromosomes from some offspring, these mate with females who then lay eggs which overwinter. I like this about aphids, it's neat.

Next week, I hope there will be an animal and maybe even not an insect.

Until then, stay safe, and look out for dying shrubberies.

Animal of the Week -- June 23, 2008

It can't possibly have escaped your attention that this week in the UK is National Insect Week -- so naturally I am going to join in the celebrations by nominating an insect as this week's animal. But what to go for? Something gaudy and noticeable, such as the swallowtail butterfly or hummingbird hawk moth, both occasional visitors to these shores? Or maybe our largest insect, the stag beetle, which reaches lengths of up to 7 cm including its antlers? Perhaps a lovely lazy bumble bee, many species of which are in decline all over the UK, or our rarest insect the streaked bombardier beetle, which repels predators by squirting a noxious combination of hydrogen peroxide and hydroquinone that explodes with a noisome smell and a loud pop. Damn it! Perhaps I should do all insects. The most diverse group of organisms on the planet perhaps accounting for 90% of species diversity -- although that might take me some time.

Nah, tell you what, among all the glamorous options, let's celebrate a much maligned species which is one of my favourites, Lepisma saccharina (silverfish). These primitive wingless insects (contrary to some misinformation, not all have wings) have remained largely unchanged for the past 300 million years. I guess they get a bad rep for living among rotting wood and damp places in bathrooms, but really they are just probably eating shampoo residue and other stray starch and cellulose based products such as wallpaper paste, glues, or toast. While they might occasionally start nibbling at the gum holding books together, or in rare times of famine nibble at leather or natural fibres, they're probably not doing much damage to your stuff, they just like damp places... and if your books are damp enough to attract silverfish, you've got damp books anyway.

Most commonly seen fleetingly as they retreat from bright light, nocturnal silverfish glide gracefully with glaucous iridescence, undulating like a minnow across your bathroom floor. I think they are quite beautiful. According to wikipedia, "The reproduction of silverfish is preceded by a "love dance", involving three phases, which may last over half an hour. In the first phase, the male and female stand face to face, their trembling antennae touching, then repeatedly back off and return to this position. In the second phase the male runs away and the female chases him. In the third phase the male and female stand side by side and head-to-tail, with the male vibrating his tail against the female", after which the male deposits a gift of sperm, wrapped in gossamer, which the female picks up. How much of the first bit is true I am not sure, the second bit about the giftwrapped seminal present, however, is true. Although they stop short of a post-coital smoke.

So cut these most ancient but graceful creatures some slack for the remainder of National Insect Week, June 23–29.