Pros: 1  Works equally well in open terrain, under cover or in a gym. 2  Accurate on flat or hilly terrain and when making quick, sharp turns (e.g., when trail running or on an indoor track). 3  Lightweight design is sleeker than most GPS-enabled SDMs.
Definitions for mass extinction. Here are all the possible meanings and translations of the word mass extinction. Wiktionary(0.00 / 0 votes)Rate this definition: mass extinction(Noun) A sharp decrease in the total number of species in a relatively short period of time.
Mass Extinctions Change the Rules of Evolution. A reinterpretation of the fossil record suggests a new answer to one of evolutionâs existential questions: whether global mass extinctions are just short-term diversions in lifeâs preordained course, or send life careening down wholly new paths. Some scientists have suggested the former.