About: http://webisa.webdatacommons.org/165830708

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	According to Hildebrand, whale calls used to average 22Hz, whereas today the frequency is around 15Hz. ???These animals have a finite lung capacity, so their songs are a trade off between frequency and volume.
http://www.w3.org/ns/prov#wasQuotedFrom	sandiegoreader.com