Answering evolutionary questions: A guide for mechanistic biologists
Masel J and Promislow DE. Bioessays 2016 Jul; 38(7):704-11
PMID: 27151396 DOI: 10.1002/bies.201600029
Gupta B: F1000Prime Recommendation of [Masel J and Promislow DE, Bioessays 2016, 38(7):704-11].
In F1000Prime, 31 Oct 2016; DOI: 10.3410/f.726338043.793524332.
This primer takes an interesting approach to teaching how one could design good hypotheses to answer evolutionary questions. It is aimed at researchers who are trained to investigate mechanistic problems in cellular, molecular and developmental biology, but should also be helpful to many others.
The traditional divide between mechanistic and evolutionary biologists is that while mechanistic people are busy asking 'how' questions (e.g., how is the aging process controlled?), evolutionary groups are more focused on 'why' questions (e.g., why do animals age?). However, few mechanistic researchers want to cross the bridge, and they will benefit from this guide.
The authors discuss three types of hypotheses when asking an evolutionary question: null or intrinsic, by-product, and adaptive. Using examples such as aging and protein thermostability, they walk through each of these hypotheses and stress the need to consider adaptive hypotheses only if the other two (intrinsic and by-product) are unable to serve as strong justifications. The rationale is that adaptive explanation is so easy to propose that it may be incorrectly used if not carefully addressed. Overall, I enjoyed reading the review and the writing style of the authors.