Editing Bohr effect (section)

=== Marine mammals ===
An exception to the otherwise well-supported link between animal body size and the sensitivity of its haemoglobin to changes in pH was discovered in 1961.<ref name=":0">{{Cite journal|last=Riggs|first=Austen|date=1961-04-01|title=Bohr Effect in the Hæmoglobins of Marine Mammals|journal=Nature|language=en|volume=190|issue=4770|pages=94–95|doi=10.1038/190094a0|pmid=13741621|bibcode=1961Natur.190...94R|s2cid=26899569}}</ref> Based on their size and weight, many [[marine mammal]]s were hypothesized to have a very low, almost negligible Bohr effect.<ref name=":1" /> However, when their blood was examined, this was not the case. [[Humpback whale]]s weighing 41,000 kilograms had an observed <math display="inline">{\scriptstyle \Delta \log (P_{50}) \over \Delta \text{pH}}</math> value of 0.82, which is roughly equivalent to the Bohr effect magnitude in a 0.57&nbsp;kg [[guinea pig]].<ref name=":1">{{Cite journal|last=Riggs|first=Austen|date=1960-03-01|title=The Nature and Significance of the Bohr Effect in Mammalian Hemoglobins|journal=The Journal of General Physiology|language=en|volume=43|issue=4|pages=737–752|doi=10.1085/jgp.43.4.737|issn=0022-1295|pmid=19873527|pmc=2195025}}</ref> This extremely strong Bohr effect is hypothesized to be one of marine mammals' many adaptations for deep, long dives, as it allows for virtually all of the bound oxygen on haemoglobin to dissociate and supply the whale's body while it is underwater.<ref name=":0" /> Examination of other marine mammal species supports this. In [[pilot whale]]s and [[porpoise]]s, which are primarily surface feeders and seldom dive for more than a few minutes, the <math display="inline">{\scriptstyle \Delta \log (P_{50}) \over \Delta \text{pH}}</math>was 0.52, comparable to a [[Cattle|cow]],<ref name=":1" /> which is much closer to the expected Bohr effect magnitude for animals of their size.<ref name=":0" />