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!