Bats are unique mammals. This note discusses some questions regarding bat evolution including why they are nocturnal and why they can echolocate. It is hypothesized that echolocation was necessary for bats to survive the period of limited visibility that followed the Cretaceous-Paleogene (K-Pg) extinction event.
Cite
@article{arxiv.1705.03403,
title = {The K-Pg event as a key to bat evolution},
author = {Barak Kol},
journal= {arXiv preprint arXiv:1705.03403},
year = {2017}
}