Some real puzzles will occupy Dave during the coming years. It is obvious that there are winners and losers among the creatures that survive mass extinctions, but not all of the winners explode to fill vacant ecological niches. Testing ideas on the reasons behind the different fates of the survivors will be an interesting challenge. This turns out to be true for reef systems only. Sandy tropical marine shelves show good recovery rates.
Some groups survive and then fade away afterwards.
Lots of groups survive with reduced numbers, only to disappear later. Apparently after an extinction event the world isn t risk-free for the survivors. There is more sorting out going on. More groups that survive an extinction interval die off shortly afterward than is typical for the background level over other quiet times . In addition to this full menu of knotty problems, Dave has been working most recently on latitudinal diversity gradients in an ongoing collaboration with DOGS graduate Kaustuv Roy, now on the faculty at the University of California, San Diego.