The value of specimens of all ages
posted November 09th, 2011
When I talked to my colleagues about using this photo of dead baby birds in a blog, several felt it might bother people, so I have been debating about whether or not I should put it up. But as I saw several forensic crime shows on TV, I decided that, as a society, we seem to be getting more accustomed to scenes like this when there might be a question that can be answered. So, my goal is not to offend anyone with this, but I think the photo does make an important visual contribution to what I wanted to write about the value of collections during the breeding season. I took the accompanying photos last week as Adjunct Curator Dave Willard, Collections Assistant Mary Hennen, and Bird Division volunteer (and long-time Museum collections-database guru) Peter Lowther were preparing fluid specimens of a large number of baby birds of various common species that have come to us through the various salvage programs that Dave has overseen over the last several years. This means that all these specimens died despite efforts to save them and they eventually were given to us. Dave et al. were taking tissue from each specimen for cryogenic storage, and then the specimens were injected with formalin. They will be put into our fluid collection with other bird specimens preserved similarly. The data will be available on-line and the specimens will be preserved in perpetuity for researchers.
What got my attention with respect to wanting to take this photo was that all the baby birds in this picture are American Robins (Turdus migratorius). So, to me what the photo illustrates effectively is the amazing development one species goes through from hatching to fledging. For American Robins, hatching to fledging takes just 14-16 days! So these salvaged specimens document the stages that hatchlings of Turdus migratorius go through to become juveniles capable of flight and their first migration. At the same time, something else struck me. There are 65 species in the genus Turdus, and I would hazard a guess that there may be no specimens of non-fledged young for more than half of these species in any museum collection in the world. I further would guess that this is true for well over half of the more than 10,000 species of birds in the world.
There is a long history of excellent research following nests of birds by ornithologists who measure the young and band them. Collections of developmental series provide extremely valuable complimentary data to this research. For example, the fluid specimens allow one to study how muscles, bones and organs develop, so they provide data that are not easily obtained in any other way. These specimens may harbor clues about the myriad of complications that face all species as they try to raise young, from birth defects to environmental hazards. Having the specimen (along with tissue) means that far into the future comparisons can be made to subsequent populations (and other species) that would not be possible otherwise.
Any of us with children and access to the web know how much scientific information there is about human children, after all this is the period when so much that will effect the future of those individuals is happening. There is an entire field of Pediatrics with many subfields devoted to the study of non-adult humans. So it seems strange that for most other species with which we share the planet, even relatively easy to study and understand animals, like birds, we often have little or limited information on how young develop.
While I can understand that some might look on this photo and see nothing more than a grisly documentation that not all young birds reach adulthood or even get far beyond the hatching stage, what I see is the potential to investigate a host of questions now and into the future about American Robins. As stewards of the planet, humans owe it to the rest of biodiversity to have better data and knowledge about comparative development of young because I suspect, just a with humans, it could teach us an awful lot about how all these species are or are not coping with a world they are forced to share with 7 billion people.
If you want to read another blog post about some different kinds of specimen preparations in our collection, check out what our volunteer Meera Sethi posted recently: http://www.scienceessayist.com. (Thanks Meera!)