“We should be extremely cautious in concluding that an organ could not have been formed by transitional gradations of some kind. Numerous cases could be given amongst the lower animals of the same organ performing at the same time wholly distinct functions; thus in the larva of the dragonfly… the alimentary canal respires, digests and excretes.”
It struck me recently that I have been making use of a lot of practically-free services provided by a variety of communities, but that I have not necessarily been giving anything back in return.Read More »
The Committee for the Advancement of Scientific Skepticism (CASS) was asked recently to take part in a discussion of the relationship between religion and the environment. A number of questions were put to the group, and I have reproduced those questions below with some of my (brief) answers. Feel free to chip-in in the comments – I’d be interested to hear what others think!Read More »
Intelligence can be defined as the ability to solve novel problems. In other words, many examples of “animal intelligence” wouldn’t count because of the limited range of situations within which they are able to act. Examples might include squirrels caching nuts and finding them again or the ability of drongos to mimic the alarm calls of meerkats to scare them off and steal their food. A true demonstration of intelligence requires that an animal be able to solve a problem with which it has no familiarity. The kea is an example of an animal that has a remarkable capacity to do just this (h/t Jerry Coyne):
So, I get asked all the time “what’s the difference between dragonflies and damselflies?” Here is my response:
The katydids (or, as my compatriots and I know them better, the bush-crickets) can probably lay claim to a number of titles in the animal world. Here are just a few:
A few weeks ago I cycled up into Gatineau Park, just outside of Ottawa in Quebec. It’s nice having wilderness this close to the city, even if I don’t use it enough! My target was Pink Lake, about 8km inside the park boundary and that made for a 30km round trip. It’s hard work getting there (the lookout in the photo is about 120m or 400 feet above when I started) but good fun free-wheeling most of the way home. I didn’t know anything about the lake (there are a lot of them around and I assumed it was just like the others). However, when I saw the interpretation signs at the site I noticed it was “meromictic”. What this means is that the lake waters never entirely mix and it produces a fairly special environment for life. The signs gave some information about the biological implications which I thought I would share.
I recently came across this neat video of an ant colony dismantling a dead gecko.
I have been involved in “climate space modelling” for a few years now. This is an approach that uses observations of a given species to determine the range of environmental variables under which it will occur. Once you know what the limits of its tolerance are, you can predict where the species will occur. For example, let’s say that a damselfly (of course I’m using a hypothetical damselfly) can live at temperature of between 10 and 20 degrees and precipitation has to be between 200mm and 500mm per year. Warmer, wetter, cooler or drier than that and it can’t survive. We can use these limits to predict (i) where the species currently exists but has not been recorded, and (ii) where the species might exist in the future as the climate changes.