I think the right answer is 'no'. (So says this evolution website: "These bones resemble those of other mammals, but are only weakly developed in the whale and have no apparent function.") They had a function for whales' ancestors who walked on land in the distant past and needed hip bones for their leg bones to attach to. But lacking legs, whales have no use for hip bones, rendering these structures without function in the present.This is a problem for evolutionary accounts of function. On these accounts, the function of the whale's hip bones is something like connecting up with the whale's leg bones. That's because evolutionary accounts of function are historical. On such accounts, the selection pressures that caused a particular part to exist are what gives it its function. I'm fine with saying that whale hip bones had the function of connecting with legs in the past, when they were in whale ancestors who had legs. They just don't have it now.
Maybe we could build a better account of function by looking at the way that some part relates to an animal's present interests. This gives many of the same intuitive answers as to what the function of a particular part is, but it deals better with vestigial structures that have lost their function. I don't see any reason why the function of some part needs to connect to the process that produced it -- natural objects that we find can be put to some purpose, and thus acquire a function. If I find a bunch of rocks and use them as ballast in my submarine, their function is to add weight so that the sub will go down, even though that has nothing to do with the process that produced them.
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Patrick Forber deals with some of these issues in the context of Nietzsche's Darwinian (or non-Darwian, depending on how you view the issues) commitments, in a paper available here.
Neil, of course it's true that things can acquire functions by intervention of the intentions of some cognitive agent, as with the rocks used as ballast. This is why folks in the literature often distinguish between proper function and acquired function, where the former is meant to be explained by appeal to evolutionary mechanism and the latter is not. Also, there is the well-known phenomenon of accidental developments which accompany evolutionary mechanism. These unintended byproducts are often called "spandrels" after the imagery of the spandrels that appear between the arches of cathedrals: these spaces were not the purpose of the arches, but here they are, and they make a nice place to put a painting. It seems to me like the whale's hip bones can be thought of as spandrels of evolution, in which case the question of their function does not arise. We only aim to explain the function of things which were selected for in the evolutionary process, not all the other accidental features.
Colin, I guess I'm wondering why we need an account of function that goes beyond acquired function. What work is function supposed to do for us that acquired function wouldn't be able to achieve?
Well we want an explanation of certain facts that biologists appeal to, such as the fact that the function of the heart is to pump blood. It seems totally legitimate to appeal to such 'function facts' to explain biological phenomena, but also seems that these functions are not acquired by intelligent design.
Doesn't acquired function do a fine job with the heart? It implies that the function of my heart is to pump blood, because that's pretty important to my interests. I don't know why we have to do some kind of historical thing to get that result.
Hi Neil,
Robert Cummins and I defend an 'ahistorical' account of functions in Blackwell's recently published "Contemporary Debates in Philosophy of Biology" (Mark Perlman defends the selectionist account). Here's the abstract of our paper:
"Attributions of function are ubiquitous in biology and the sciences generally, and yet philosophers and scientists disagree over how we should understand functions and functional attributions. At issue are the explanatory and normative dimensions of functions and functional attributions, and in this paper we characterize two well-known accounts of functions--what we will call systematic and selectionist accounts--and compare and evaluate their respective stances on these dimensions. We argue that whereas systematic accounts provide an approach to functions that is indispensable to biology and the rest of science, selectionist accounts do not. Furthermore, we argue that selectionist accounts introduce a conception of normativity that has no legitimate place in science, while systematic accounts do not. Our conclusion is that selectionist accounts of functions are deeply flawed, and that the attempt to ground function in selection history is a mistake."
If you get a chance to read the articles, I'd like to hear what you think! (I apologize for the self-serving plug).
Martin Roth
As I'm using the term an acquired function is something imparted by the intentions of a cognitive agent. For example, the pigs intestine used to make sausage acquire the function of holding the meat together. Before the pig was killed, the function of the intestine was to digest and distribute nutrients to the rest of the pig's body. Their function qua sausage casing was acquired by design, but their function qua organ was not acquired in this way. What explains the 'natural fact' that intestines function to serve the purpose they do? Selection for that purpose.
Terminology aside, here is what might be odd about your kind of interest-relative explanation. Suppose a pig is born with an autoimmune disease such that she has a severe, and lethal reaction to folic acid. Suppose she also suffers from a random mutation of the intestine which prevents it from digesting folic acid. This organ is serving the interests of this particular organism, but it is also malfunctioning. What explains the malfunction other than a historical, evolutionary explanation?
That looks nice, Martin! I'd like to take a look at it.
I think the interest-relative view can account for both things I think about the pig case, Colin. To some extent I have the intuition that the stomach is malfunctioning, and this can be accounted for with regard to other interests. For example, it would probably be in the pig's interests to have folic acid in some of her other metabolic processes so she wouldn't grow an extra nose or whatever. It's relative to these interests that the stomach is malfunctioning. Of course, there are other interests relative to which the stomach is functioning properly, namely not dying of the autoimmune disease. Really if I were the pig and I somehow came to know about how my stomach worked, I'd regard it as a malfunction if it started absorbing folic acid and killing me.
The hipbones of a whale are so that they can wear pants.
Idiots... those bones are required for reproducing! They have nothing to do with walking or the ignorant theory of evolution. Not everything you're taught is true...
Think for your damn selves. This bullshit was proven wrong many years ago.
Greg, there is no scientific evidence that the bones are "required for reproducing". It's creationist nonsense.
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