Editing Gentoo penguin (section)

==Physiology==
[[File:Gentoo Penguin AdF.jpg|thumb|left|220px|Gentoo penguins in Antarctica, walking along a "penguin highway", a path that joins the sea and their nesting area on a rocky outcrop]] The gentoos' diet is high in salt, as they eat organisms with relatively the same salinity as seawater, which can lead to complications associated with high sodium concentrations in the body, especially for gentoo chicks. To counteract this, gentoos, as well as many other marine bird species, have a highly developed [[salt gland]] located above their eyes that takes the high concentration of sodium within the body and produces a highly saline-concentrated solution that drips out of the body from the tip of the beak.<ref>{{cite journal|author=Schmidt-Nielsen, K. |title=The Salt-Secreting Gland of Marine Birds|journal=Circulation|volume=21|issue=5|pages=955–967|doi=10.1161/01.cir.21.5.955|pmid=14443123|year=1960|doi-access=free}}</ref>

Gentoo penguins do not store as much fat as Adélie penguins, their closest relative; gentoos require less energy investment when hunting because the net gain of energy after hunting is greater in gentoos than Adélies.<ref>{{cite journal|author1=D’Amico, V. L.|author2= Coria, N.|author3= Palacios, M. G.|author4= Barbosa, A.|author5= Bertellotti, M. |title=Physiological differences between two overlapped breeding Antarctic penguins in a global change perspective|journal=Polar Biology|volume=39|pages=57–64|doi=10.1007/s00300-014-1604-9|year=2016|issue= 1|bibcode= 2016PoBio..39...57D|hdl=10261/156947|s2cid=17563166|hdl-access=free}}</ref> As embryos, gentoos require a lot of energy to develop.  Oxygen consumption is high for a developing gentoo embryo. As the embryo grows and requires more oxygen, consumption increases exponentially until the gentoo chick hatches. By then, the chick is consuming around 1800 ml O<sub>2</sub> per day.<ref>{{cite journal|author=Actams, N. J. |title= Embryonic metabolism, energy budgets and cost of production of the king ''Aptenodytes patagonicus'' and gentoo ''Pygoscelis papua'' penguin eggs|journal= Comparative Biochemistry and Physiology Part A: Physiology|volume= 101|issue= 3|pages= 497–503|doi=10.1016/0300-9629(92)90501-g|year= 1992}}</ref>