Milk evolution with emphasis on the Atlantogenata

The milk composition of each species is unique, because it has evolved according to specific needs and adaptation to the environment. As milk data from more species became available, an evolutionary trend shows a phylogenetic distinction between Eutherian taxa regarding milk composition. For example, differences in the composition and properties of nutrients have been reported between carnivores and herbivores, as well as between ruminants and non-ruminants. Although limited, data of the three subclades of the Eutheria (Xenarthra, Afrotheria and Boreoeutheria) suggest that a phylogenetic distinction in milk composition may also exist between them. In this review, the validity of such a distinction is investigated with emphasis on the Atlantogenata. Keywords: α-lactalbumin, casein, fatty acid, lactose, oligosaccharid