But, comparative anatomy against modern, still-living species -- especially those related to the extinct ones -- also plays a big role. And this is where paleontology can get a bit dicey for animal-lovers.
Take, for instance, last week's study concluding that dinosaurs were about 10 percent larger than previously thought (for a layman's-eye view, go here). The study used "salvaged remains" from alligators and various bird species to determine the relationship in dinosaurs between the morphologies of their joint bones and their estimated heights, concluding that because traditional estimates did not tend to account for missing cartilage, many dinosaur species may have been significantly larger than once thought.
The methods for determining this, at first glance, seem rather ghoulish and exploitative (emphasis added):
Extant alligators and birds were used to establish an objective basis for inferences about cartilaginous articular structures in such extinct archosaur clades as non-avian dinosaurs. Limb elements of alligators, ostriches, and other birds were dissected, disarticulated, and defleshed. Lengths and condylar shapes of elements with intact epiphyses were measured. Limbs were subsequently completely skeletonized and the measurements repeated.This is the kind of thing that, when I first started studying paleontology, would set off alarm bells. Had I made a devil's bargain? Could it truly be that even this field of science exploits and tortures animals for experimentation? Was I going to have to become a history major, after all?
Well, maybe not. Many such comparative anatomy papers contain ethical statements about the sources of their animal subjects, providing animal activists and other readers with a rather laudable level of transparency. This paper is no different:
All research was conducted on salvaged animal specimens and no approval from Ohio University Institutional Animal Care and Use Committee was necessary.More detail is given later:
The alligator sample consisted of 15 specimens obtained from the Rockefeller Wildlife Refuge (Grand Chenier, LA) ranging in size from about 0.5 m to 2.5 m total length. Ostriches were obtained from a commercial processing center, and all individuals were of roughly equivalent size.No mention is made of where the researchers obtained their other bird specimens, however.
Salvaged animal specimens are generally obtained from animals who weren't killed specifically for the research in question; i.e., those who died of natural causes in nature preserves or the wild, donated pet cadavers, etc. But some, like the ostriches here, are collected from "commercial processing centers," implying a link to factory farming or slaughter for food.
I'm of two minds about this. On the one hand, I'm all in favor of obtaining and studying animal remains from humane sources and donations. On the other, I'm troubled by the possible link to industrial animal exploitation, and saddened that even potentially cruelty-free sciences like paleontology rely on such base meanness to other forms of life (albeit indirectly, in this case).
The argument that "they'd be killed anyway" (likely applicable to the ostriches) has never sat well with me. That's the sort of muddy moral thinking that justifies factory farming, too. But, I think there might be room to draw a distinction between deliberate cruelty and fruits of a tainted tree. I doubt the ostriches in this study were killed specifically for the paleontological team; a more likely scenario is that the lab contacted the ostrich supplier, asking if they had any already-deceased but well-preserved carcasses.
I have no idea what sort of protocols the Witmer Lab has to ensure that their ostriches weren't already dead, but I'm willing to give them the benefit of the doubt. If anything, it's their supplier I'd be suspicious of.
I confess that an unwillingness to confront the thorny moral labyrinth here is one reason I chose to focus my animal activism on factory farming and veganism (the other being, of course, that this is the single largest source of the greatest suffering inflicted on animals). But, as I advance forward in my studies, I will likely have to face this and sort it out, once and for all.
If I'm lucky, I could secure a position with such a lab that involved ensuring ethical transparency from suppliers. But grad school is quite a ways off for me at the moment.
In the meantime, I'll keep vigil, and take comfort in knowing that I'll most likely never have to be part of a study that requires me to work with modern animals.
Another reason to love field work!