Context: Recent research indicates that the specialized animals that formed complex ecosystems, with high biodiversity, complex food webs and a variety of niches, took much longer to reestablish, recovery did not begin until the start of the mid-Triassic, 4M to 6M years after the extinction and was not complete until 30M years after the Permian–Triassic extinction event. Animal life was then dominated by various archosaurian reptiles: dinosaurs, pterosaurs, and aquatic reptiles such as ichthyosaurs, plesiosaurs, and mosasaurs.

Question: What type of animals took longer to reestablish?
Answer: specialized animals

Question: When did recovery of these diverse animals begin?
Answer: mid-Triassic

Question: How long after the Permian-Triassic extinction did animal recovery take to completion?
Answer: 30M years

Question: What dominated animal life in the Triassic?
Answer: reptiles

Question: How many years after the extinction did animal recovery begin?
Answer: 4M to 6M

Question: What type of animals were especially quick to reestablish?
Answer: Unanswerable

Question: The recovery of many species failed during what period of the Triassic?
Answer: Unanswerable

Question: What animal life was most at risk in the Triassic?
Answer: Unanswerable

Question: How many years of recovery did the extinction interrupt?
Answer: Unanswerable