Editing Anti-predator adaptation (section)

===Selfish herd===

{{main |Selfish herd theory}}

The selfish herd theory was proposed by [[W.D. Hamilton]] to explain why animals seek central positions in a group.<ref>{{Cite journal |last1=Hamilton |author-link=W. D. Hamilton |first1=W. |title=Geometry for the selfish herd |journal=Journal of Theoretical Biology |volume=31 |issue=2 |pages=295–311 |date=1971 |pmid=5104951 |doi=10.1016/0022-5193(71)90189-5|bibcode=1971JThBi..31..295H }}</ref> The theory's central idea is to reduce the individual's domain of danger. A domain of danger is the area within the group in which the individual is more likely to be attacked by a predator. The center of the group has the lowest domain of danger, so animals are predicted to strive constantly to gain this position. Testing Hamilton's selfish herd effect, Alta De Vos and Justin O'Rainn (2010) studied [[brown fur seal]] predation from [[great white shark]]s. Using decoy seals, the researchers varied the distance between the decoys to produce different domains of danger. The seals with a greater domain of danger had an increased risk of shark attack.<ref name="De Vos ORiain 2009">{{cite journal |last1=De Vos |first1=A. |last2=O'Riain |first2=M. J. |title=Sharks shape the geometry of a selfish seal herd: experimental evidence from seal decoys |journal=Biology Letters |volume=6 |issue=1 |date=September 2009 |doi=10.1098/rsbl.2009.0628 |pmid=19793737 |pmc=2817263 |pages=48–50}}</ref>