Why Mice?
Jay Fox has put a fair amount of time into thinking about the Methuselah Mouse Prize and whether or not other animals - such as flies, for example - would be a better choice for present day healthy life extension research. In a recent post at Longevity First, he makes the case for mice:
Shrews have perhaps the perfect lifespan for studies, but are not well understood. Mice, on the other hand, live about three years, and the oldest mouse ever recorded lived a week shy of five years. Also, next to humans, they are one of the most thoroughly studied species in the animal kingdom.Performing an anti-aging treatment that doubles lifespan in mice would only take a decade at most to test, compared to a century in chimps. In middle-aged mice, a treatment could be tested in less than five years, compared to decades in chimps. A study in shrews would be even faster, but the studies would take longer to design and longer to validate, given the poor knowledge base the science community has to work with in shrews.
Thus, when all is said and done, mice really are the best choice for studying aging.
The choice of mice for the Methuselah Mouse Prize was made in full knowledge of the various trade-offs between different species. How well we understand their biochemistry; how long they live; how costly experiments will be; how many laboratories and scientists are equipped to participate; what duration do we expect for the Prize initiative. Note that there is no one correct answer here - even after walking through these points, a case could still be made for good science to be done with flies or zebrafish.
It is hard to argue with success, however. The Methuselah Mouse Prize is doing well at its first intended goal - to attract attention to longevity research and educate the public. The next step, as the prize fund grows, is to get the science done. As we advance down that path, I see a role for smaller, faster prizes focusing on species with shorter life spans that require less costly laboratories.
To clarify the comment that "a case could still be made for good science to be done with flies or zebrafish", it isn't really zerbrafish that would be appropriate, but rather killifish (as a poster at one of the links mentions). Killifish have a substantially shorter lifepsan than zebrafish, making lifespan experiments quicker and far cheaper due to both the reduced time and the reduced per diem for each animal. Killifish probably are not getting the attention in the aging community that they deserve.