The ecological pyramid is smaller at the top due to the lower amount of species to fit into the category (diversity is decreased, and the higher, the more suppressed the energy is in the animals/species).
Many organic compounds are ignitable, putting them in direct flame may cause fires or combustion. it is possible to start a fire on a hot plate, but typically hot plates are not heated as high and the temperature is somewhat controll-able... you can not control the temperature of a bunsen burner very easily i would not through acetone or ethanol on a hot plate, as it can catch on fire or cause burns, but it's much worse with the bunsen burner.
Birds, Salamanders and Sharks are all Endotherms and can manipulate their body temperatures.
A large asteroid or comet impacted the earth.
