Monday, April 25, 2011

Animal of the Week April 25, 2011 -- AVnimal of the week

Many is the time that people have tried to make suggestions for animals of the week. But I've not once succumbed despite please from close friends, celebrities, and my niece and nephew -- AOTW is my autocracy. But this week, just this week, I'm injecting a little democracy. And I'm going to ask you to vote for your preferred species. Let's start with three species, Pelophylax lessonae (pool frog), Pelophylax ridibundus (marsh frog), and Pelophylax esculentus (edible frog).
Marsh frog
The pool frog and the marsh frog are the descendants of a single species that was divided into two populations when glaciers covered much of Europe during the last ice age. When Europe's glaciers receded, the two populations emerged from their refuges in southern Europe as distinct species. The marsh frog larger with longer legs and the pool frog with white vocal sacks and short legs. But although they were distinct species, where they met they could interbreed, and they did, producing the hybrid edible frog.

Edible frog
But the edible frog -- intermediate size, intermediate legs, a compromise of the two -- actually behaves as a (slightly peculiar) species in its own right, unlike many other hybrids which are infertile and can't breed. The offspring of two adult edible frogs are typically fatally deformed, but when female edible frogs reproduce with males of either of the other two species they produce viable edible frogs. The situation is complicated further by the fact that in northern Denmark and southern Sweden, edible frogs seem to reproduce quite happily without the help of the parent species.

Pool frog
The pool frog is native to the UK, but both other species exist here as introductions. Mostly the species eat flies, dragonflies, crickets, worms, and other invertebrates. The marsh frogs, the largest, can eat other amphibians and small mammals! These three frogs form the green-frog species complex. All very typical frogs, fairly green and largely aquatic, living in ponds, lakes, and slow flowing water -- let's call these three mainstream frogs.

To increase the democratic pool, let's recall the other two anurans to have featured as animals of the week, the mouth-brooding platypus frog and the brutish, invasive cane toad.

Perhaps you like the smallness of the pool frog, or you appreciate the fact that it made it to the UK on its own. Perhaps large size and long legs float your boat and the marsh frog would be your favourite. Perhaps you think that you like the quirkiness of the middle-ground edible frog. What do you think other readers of AOTW will like? Perhaps you really don't like the bastard hybrid edible frog, but like their parent species. Do green frogs just not do it for you at all and you'd rather plump for a cane toad or a platypus frog.

Well, you don't have to select just one, you can rank them all in order of preference from your favourite 1 lo least favourite 5. You can select just your favourite one; or you can select just two, three, or four. The frog with the fewest first preferences (1s) in the first round will be eliminated, and the votes recast, counting the second preferences of those whose first preference has been eliminated.

The ballot sheet is randomly assigned as

A: Marsh

B: Edible

C: Cane

D: Platypus

E: Pool

 Let me know your preferences for anuran animals of the week by emailing me at animal_oftheweek@yahoo.co.uk, by twittering @animaloftheweek (please #aotw), or by posting a blog comment?

Choose your frog by an alternative voting system: just like the Conservative party did theirs!

Monday, April 11, 2011

Animal of the Week April 11, 2011 -- Doctor, doctor, you look like a fish

Yamada Kazuki
It can never be said I am not riding the crest of coming fads... it's only taken me five years since the first fish spa opened in Japan to feature Garra rufa (doctor fish, nibble fish, kangal fish) as animal of the week!

Also known as reddish log suckers, in the rivers of their homelands in the Middle East, these small members of the carp family use their sucker-like mouths to hoover up algae, detritus, and invertebrates. In aquariums, these fish help prevent algal build up. But if you keep em hungry, these fish happily view human skin as a feeding surface, and they rasp off dead and diseased skin. 

This fish massage therapy has been used for many years in Turkey, where patients have visited warm springs to have the fish nibble off their dermatitis and psoriasis. In the past few years the use of fish in beauty therapy has proliferated, with spas using the logsuckers -- although marketing materials show a preference for the name "doctor fish" for some reason -- opening up in Japan, Korea, the USA, Europe, and in 2010 the Sheffield, UK. In the USA, cosmetology (no, I didn't make that up -- someone else did) regulators have decreed that fish therapy should not be used because their code requires that equipment is sterilised after use, and you can't really autoclave a fish. Hmmmmmm, whitebait.

Most fish therapy involves simply dipping your feet in a tank of fish and having them pick away the dead skin, corns, and athletes' foot -- that's what you can get in the market at Camden from time to time, where the concerns about not being able to sterilise the tanks between treatment really strike home. I put a Ben Goldacre mask on for a moment and looked for mentions of Garra rufa in PubMed to see if any studies had been done on their use in the treatment of skin diseases. To date, one pilot study was archived showing that a course of fish therapy dramatically improved moderate to severe psoriasis... well, a course of fish therapy combined with UVA treatment... combined with UVA treatment and post UVA massage with shea butter and aloe vera... well fish therapy improved psoriasis (when given with UVA and unguent) in a self-selected self-reporting sample of 67 patients in a study published in the journal Evidence-Based Complementary and Alternative Medicine (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1697753/?tool=pubmed).  Since 2006, nothing.

The interest in fish "therapy" grows unabated, and you can even buy home kits. In Singapore, a fish massage tank start-up kit will set you back just 175 Singapore dollars (£85). And why wouldn't you get one? See this testimony from one happy customer:

"Now I'm able to enjoy fish spa everyday with my family members. We have so much fun feeding the fish with our leg while watching our favourite television programme. By the way, my skin is now extremely soft and smooth."
http://www.yourdoctorfishspa.com/ 

Monday, April 04, 2011

Animal of the Week April 4, 2011 -- One does not a summer make

Malene Thyssen
Taking a step back from what I've got in my garden this week... I've not yet seen a single one of this week's animal in my garden, although it is only a matter of time before I see Hirundo rustica (barn swallow) if not in the tiny space out back, then skimming over the top of the gardens or flitting inches from the ground in Regents Park or Hampstead Heath.

Swallows are one of those species of impressively aerial birds including martins and swifts that arrive in spring to feast on the emerging flying insects as they raise their families. One way to tell the birds apart is the place in the air column they choose to feed. Sickle-winged swifts fly high overhead, house martins swoop around above rooftops, swallows often feed inches above the grass of meadows or the surface waters of rivers and lakes their buoyant graceful flight bringing them impossibly close to crashing in pursuit of supper. Close to, swallows are easily distinguished by their oily blue back and their red throats.

I saw swallows a month ago in Seville, bouncing off the surface of the Guadalquivir, and it seems that now they have caught up with me and made it to the UK, with the Wildfowl and Wetlands Trust twitter feed telling me they've arrived at the Barnes Wetlands Centre in south west London.

The barn swallow is one of the most widespread birds in the world, with few countries where they are not to be seen at some point during the year. The birds follow the spring north, nesting from north Africa, Mexico, and northern India all the way up to the arctic circle. Then, as the nights draw in in the north, they head back south to Central and South America, sub-Saharan Africa, south Asia and northern Australia. Birds arriving in England now may have come all the way from Cape Town.

Individual birds cover over 11 000 km in their migration each year. And the estimated worldwide population of 190 million has a range that covers 51 million square-kilometres, which is more than a third of the total land surface area of the earth.

Sorry Aristotle, perhaps one does not a summer make, but all over the world 190 million swallows do.