This is a sign that one of the genetic innovations that led to the development of milk occurred more than 166 million years ago, and after mammals first split from. The analysis shows that the platypus has genes for the family of milk proteins called caseins, which map together in a cluster that matches that of humans.
Platypus evolution tree Patch#
Although the platypus doesn't have nipples, it produces true milk-full of fats, sugars and proteins-which the young suck through a glandular patch on its skin.
Comparisons with the genomes of other mammals will help to date the emergence of the platypus's distinguishing characteristics and reveal the genetic events that underlie them.įor example, mammals are defined by their possession of mammary glands, which in females can produce milk. "The analysis is beginning to align these strange features with genetic innovation," says Wesley Warren of Washington University in St Louis, Missouri, the lead author of the genome analysis-a huge international project (see page 175).
Now, the structure of its genome has revealed new clues to how mammals evolved. The semi-aquatic monotreme is a venomous, duckbilled mammal that lays eggs, nurses its young and occupies a lonely twig at the end of a sparse branch of the vertebrate evolutionary tree. The platypus (Ornithorhynchus anatinus) is endemic to Australia and one of nature's oddest creatures, seemingly assembled from the spare parts of other animals. A phylogenetic tree was generated from the data of table. A draft sequence of the platypus genome reveals reptilian and mammalian elements and provides more evidence for its place in the ancestral line of animal evolution. marsupials and the platypus (a monotreme) are more closely related to each other than the.
0 kommentar(er)
