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 extinction=refers the rapid extintion of a large number of lineages scattered thoughout the tree of life. 60% species are wiped out within 1 million years. Backround extinction=lower, average rate of extinction observed when a mass extinction is not occuring.Natural.routinly Two we focus on: 1.