Genetic kin recognition and Crozier's Paradox

Genetic kin discrimination is when animals use genetic cues to determine who their close relatives are. Genetic kin discrimination would allow individuals to be nepotistic, preferentially directing cooperative help to closer relatives.

The extent to which genetic kin discrimination occurs in nature remains controversial. Evolutionary theory says that genetic kin discrimination often won't be possible, because there won't be enough genetic variation to distinguish kin from non-kin. The empirical data is mixed. There are many examples of animals using environmental cues to assess relatedness, such as 'grew up in same nest'. In contrast, while there are some examples of genetic cues, their relative role in nature remains unclear.

We will use a two-pronged approach to clarify the role of genetic kin discrimination in the natural world:
(1) We will develop theory to examine when genetic kin discrimination can be evolutionarily stable. We suggest that previous theory has come to a misleading conclusion, because it did not allow for how animals interact in the real world.
(2) We will carry out an across-species comparative study, to explain why some species use environmental cues to assess relatedness, while others use genetic cues.