Observing Frogs

By Garry | May 5th, 2010 | Category: Gaz Thoughts | No Comments »

Rainy season in Thailand is marked, amongst other methods, by an increased attendance of frogs and toads in the garden at night. This is a particularly noticeable phenomenon, far more so than any equivalent back in the UK, because it coincides with several other seasonal events from the animal kingdom.

The forerunners to the summer monsoons arrive in early May, here in Korat, though they are usually later up north in Chiang Mai (usually sometime in June), but in both locations, those first showers and downpours trigger “flying ant season” – a week or so when from dusk to midnight, every artificial light source is besieged by clouds of ants with wings.

Much larger than your regular ground dwelling ants, flying ants have been known to be collected as a protein source by Thais, for many generations. You still sometimes see Thais doing this, usually by way of a small electric light suspended over a large basin of water. The insects exhaust themselves flying around the light and fall into the water, where they are later collected for frying.

At this time too, ground-travelling ants usually up-sticks and move nest from warm sunny spots in the garden, to dry and storm-proof cavities in or under the structure of buildings. You will often see lines of them in convoy, transporting eggs, and should you interrupt their line, you’ll notice that the eggs are their top protective priority – the milky looking eggs being about the size of an uncooked rice grain, immediately become the focus of every ant in the column as they are dragged away to cover and protection. These convoys run night and day until the nest is relocated. Ants are terrified of flooding in the nest, as highlighted in the animated movie “Antz”.

Frogs on the other hand, love water. Toads do too, but they dislike falling rain. Unlike the frogs I see in the garden when the wet stuff is falling, the toads head for cover – our concrete, patio dining set, is one of their favourite storm shelters. Both the frogs and toads love flying ant season. As the confused ants circle the overhead lights and exhaust themselves, they fall to the patio floor, where they twitch and buzz with the last of their energy, then the frogs, toads, and geckoes move in for a feast.

One of the strange phenomena that I’ve observed about these evening events, is that geckoes will not move in on the dying ants if there is a toad on the patio. They’re fine if it’s only a frog, but won’t come down off the walls and ceiling in the presence of toads. There’s probably a rational explanation for this, but I’m not aware of toads considering geckoes as food prey.

Last night, as I enjoyed a late night last cigarette under the stars, I sat watching the frogs and toads chasing around the patio and yard. At some point in the proceedings, it occurred to me that toads, at speeds from a slow stroll to a medium jog, have a movement rhythm very similar to rabbits. Although frogs move similarly, there is a slight but distinct difference to the rhythm and flow of their movement. Toads, like rabbits, make much more use of their forelegs when “ambling” and recreate more closely that familiar bunny hop movement.

This observation led in turn to one of those wild “out of the blue” questions popping into my head – if toads, like crocodiles and others, are last survivors of the age of reptiles and amphibians from before man appeared on the planet, could it be possible that they are also the evolutionary ancestors of rabbits and hares? Could frogs, with their slightly different perambulation and stronger focus on “the hop”, be the pre-fur ancestors of “hopping” rodents such as gerbils and similar – the rear leg jointing orientates the same with near identical pivot points.

By tomorrow I’ll probably have forgotten such observations and questions, therefore I’ve recorded them here for posterity. Of course, I might not be the first to make such tentative questions – there’s likely whole bookshelves of research papers in university science libraries worldwide, which cover this topic. Still, I thought I’d share the idea with you as there’s not much else happening at Gaz Grange right now.