Editing Sonority hierarchy (section)

===Climates===
Maddieson and Coupé’s<ref name="Maddieson2018" /> study on 633 languages worldwide observed that some of the variation in the sonority of speech sounds in languages can be accounted for by differences in climate. The pattern follows that in warmer climatic zones, language is more sonorous compared to languages in cooler climatic zones which favour the use of consonants. To explain these differences they emphasise the influence of atmospheric absorption and turbulence within warmer, ambient air, which may disrupt the integrity of acoustic signals. Therefore, employing more sonorous sounds in a language may reduce the distortion of soundwaves in warmer climates. 
Fought and Munroe<ref name="FoughtMunroe2016">{{cite journal|last1=Fought|first1=John G.|last2=Munroe|first2=Robert L.|last3=Fought|first3=Carmen R.|last4=Good|first4=Erin M.|title=Sonority and Climate in a World Sample of Languages: Findings and Prospects|journal=Cross-Cultural Research|volume=38|issue=1|year=2016|pages=27–51|issn=1069-3971|doi=10.1177/1069397103259439|s2cid=144410953}}</ref> instead argue that these disparities in speech sounds are as a result of differences in the daily activities of individuals in different climates. Proposing that throughout history individuals residing in warmer climates tend to spend more time outdoors (likely engaging in agricultural work or social activities), therefore speech requires effective propagation of sound through the air for acoustic signals to meet the recipient over these long distances, unlike in cooler climates where people are communicating over shorter distances (spend more time indoors).
Another explanation is that languages have adapted to maintain [[homeostasis]].<ref name="Vliert2008">{{cite book|author=Evert Van de Vliert|title=Climate, Affluence, and Culture|url=https://books.google.com/books?id=zGSH2WBnqA0C&pg=PR5|date=22 December 2008|publisher=Cambridge University Press|isbn=978-1-139-47579-2|pages=5–}}</ref> [[Thermoregulation]] aims to ensure body temperature remains within a certain range of values, allowing for the proper functioning of cells. Therefore, it has been argued that differences in the regularity of phones in a language are an adaptation which helps to regulate internal bodily temperatures. Employing the use of open vowels like /a/ which is highly sonorous, requires the opening of [[Vocal tract|vocal articulators]]. This allows for air to flow out of the mouth and with it evaporating water which reduces internal bodily temperatures. In contrast, voiceless plosives like /t/ are more common in cooler climates. Producing this speech sound obstructs airflow out of the mouth due to the constriction of vocal articulators. Thus, reducing the transfer of heat out of the body, which is important for individuals residing in cooler climates.