Which of the following appeared during the mesozoic era?
a. birds
c. mammals
b. dinosaurs
d. all of the above

b. Dinosaurs

The Mesozoic Era or what they commonly refer to as the age of the dinosaurs, is yet to be established as to what really did cause the extinction of life during this era. The popular belief and what is shared to the public to be remembered is that it was caused by an asteroid impact. The dust and ashes that it produced blocked the sky for days which caused the continuous death of organisms. In other sources, it can be said that massive volcanic eruptions occurred and filled the atmosphere with carbon dioxide. With the help of microbes eating carbon dioxide, they superheated the planet because in the process, these microbes eat carbon dioxide and release methane. Another one would be massive and continuous volcanic release of lava. It wasn't exactly determined if either one or maybe all of them occurred at once to wipe out life on that era.

Hunting in the darksome fish rely on senses beyond sight. in the darkness of the marianas trench, a fish called the rattail has an extremely sensitive sense of smell. the fish uses scent, rather than sight, to steer toward food. once it's near food, the rattail uses a special organ on the bottom of its chin to guide itself by feel.marine snowone staple of the deep sea diet is "marine snow," flakes of organic, edible substances that sink down from the upper ocean. animals at the ocean's bottom find sustenance in everything from the bodies of dead creatures to fecal matter. marine snow is diverse enough to support numerous species. for instance, several species of snails and worms feed exclusively on deceased whales.microorganismsthe deep sea is an intricate ecosystem, and even the ocean floor itself plays a part. hydrothermal vents are cracks in the sea floor where erupting magma mixes with ocean water to produce plumes of hot, sulfur-rich chemicals. some microbes can use these chemicals for energy, sustaining their existence and that of the animals who depend on their roles in the deep sea food chain.