“Is There Really Natural Selection Affecting the I Frequencies (long Hair) in the Brazilian Cat Populations?”, M. Ruiz-Garcia2000 (, ; backlinks; similar)⁠:

The scientific literature on cat genetics contains a presumed typical example of natural selection affecting I frequencies (long hair) in 16 Brazilian cat populations. It has been observed that the hotter and more tropical the climate in Brazil, the lower the values of I frequencies in the cat populations.

Nevertheless, this study of some new cat populations in Latin America showed that all of them, independent of the climate, had high or very high I frequencies.

I postulate that an alternative migrational-historical hypothesis exists that explains the correlation between the I frequencies and climate characteristics (which are correlated with the latitude) without using natural selection explanations concerning the appearance of the I allele in Brazil.