Final answer:
Experimental evidence for the mutation accumulation hypothesis includes observations that enhancing DNA repair can increase organism lifespan. For the antagonistic pleiotropy hypothesis, evidence involves traits that benefit early fitness but cause aging issues, such as pathways leading to oxidative damage. Crucial evidence to distinguish between the hypotheses would involve controlled experiments that isolate the effects of either hypothesis.
Step-by-step explanation:
Experimental evidence for the mutation accumulation hypothesis includes observing increased longevity in organisms when the repair of DNA is enhanced or when mutational rates are reduced. As for the antagonistic pleiotropy hypothesis, evidence can be found in traits that have a positive effect on an organism's fitness in early life but have detrimental effects as the organism ages, such as certain metabolic pathways that may enhance energy production when young but may lead to oxidative damage in the long run.
Evidence that is consistent with both hypotheses includes observations where interventions like calorie-restriction seem to slow down both the accumulation of mutations and the detrimental effects of certain pleiotropic genes, leading to increased lifespan in some organisms but not others. The most critical evidence that could potentially support one hypothesis while falsifying the other would be controlling for environmental factors and genetic background in an experimental setting where the direct effects of either mutation accumulation or antagonistic pleiotropy can be observed independently of the other.