The mind of other species 16 Dec 2010 Jacob von Uexküll was an Estonian biologist, who among other things coined the term “Umwelt” to denote the sensory and cognitive world of a particular species. The idea has been unjustly ignored by philosophers of biology, in part because it was enthusiastically taken up by semioticians instead, in part because of his treatment of “meaning” in biology. But it is a useful distinction. Umwelt, which literally means “environment” or “surrounding world”, are those aspects of the environment to which animals respond. His case study is the tick (a tick, actually; there are lots of them): “…this eyeless animal finds the way to her watchpoint [at the top of a tall blade of grass] with the help of only its skin’s general sensitivity to light. The approach of her prey becomes apparent to this blind and deaf bandit only through her sense of smell. The odor of butyric acid, which emanates from the sebaceous follicles of all mammals, works on the tick as a signal that causes her to abandon her post (on top of the blade of grass/bush) and fall blindly downward toward her prey. If she is fortunate enough to fall on something warm (which she perceives by means of an organ sensible to a precise temperature) then she has attained her prey, the warm-blooded animal, and thereafter needs only the help of her sense of touch to find the least hairy spot possible and embed herself up to her head in the cutaneous tissue of her prey. She can now slowly suck up a stream of warm blood.” For him, the Umwelt of the tick is the odor of butyric acid, which emanates from the sebaceous follicles of all mammals, the temperature of 37 degrees celsius (corresponding to the blood of all mammals), and the hairy typology of mammals (according to Wikipedia). These three aspects of the tick’s environment are all it needs to sense. His book Forays into the worlds of animals and humans has been translated, and is now published by University of Minnesota Press. I look forward to getting a complimentary copy <grin>. [H/T Roberta Millstein] Paul Griffiths and I believe that the world of human “common sense” is the Umwelt of primates; all the things we need to negotiate to survive, mate and reproduce are the objects that common sense indicates are there, and we can tradeoff Type I (false positives) from Type II (false negatives) errors in order to do so without serious trouble. The way we perceive the world begins (but does not end!) with our shared primate Umwelt. Epistemology Evolution Metaphysics Evolution
Evolution ROUS’s? I don’t believe they exist. 15 Jan 2008 Anyone who knows the film The Princess Bride knows what happens next. Westley gets hit hard by a rodent about the size of a pitbull. However, it seems that ROUS’s (Rodents of Unusual Size) actually may have existed, in Uruguay. Nature reports that the skull of one has been discovered,… Read More
Biology Evidence and Evolution 23 Jul 2009 I have just finished doing a review (for Systematic Biology) that took me six months. It was not because I was slack. It was because I had to read it in three page segments. The book is “Evidence and Evolution: The Logic Behind the Science” (Elliott Sober) Read More
Creationism and Intelligent Design Tautology 2: The problem arises 23 Aug 2009 After Williams and others had made the comment that fitness is a tautology, it came around that the point needed to be discussed in more detail. One such discussion was by a student of Dobzhansky’s, Richard Lewontin. Read More
As usual, wikipedia is too quick to be accurate. The tick’s umwelt includes sensitivity to chemical gradients (I wouldn’t go so far as calling it ‘odor’) beyond that of butyric acid — it also has to respond to noxious stimuli. It is sensitive to other temperatures besides 37 degrees celsius, since it moves away from intense heat. And its topographic umwelt certainly is more varied than the hairy environs of mammalian surfaces, as evidenced by its habit of launching itself from grass, shrubs, low trees, etc. Finally, in arriving at a total of three aspects of its environment that the tick needs to sense, the author somehow forgets having just mentioned a general sensitivity to light. Don’t trust wikipedia.
In fact, they accurately report von Uexküll’s view. Whether he is right is another matter. But see the other comments he makes about light.
The idea has been unjustly ignored by philosophers of biology, in part because it was enthusiastically taken up by semioticians instead, in part because of his treatment of “meaning” in biology. And also because none of these philosophers were owned by a cat.
“And also because none of these philosophers were owned by a cat.” That is indeed something can only be experienced, as is the experience of what we call butyric acid, tick or human.
So the Umwelt of humans includes Toxoplasma gondii… Toxoplasma gondii is a species of parasitic protozoa in the genus Toxoplasma. The definitive host of T. gondii is the cat, but the parasite can be carried by many warm-blooded animals (birds or mammals, including humans).
Jacob von Uexküll’s grandson, also named Jacob von Uexküll, made his mark as the founder of the Right Livelihood Foundation, best known for giving out what are called the Alternative Nobel Prizes.