The pattern of mammalian evolution and the relative rate of molecular evolution

Journal Article · Mon Jan 01 00:00:00 EST 1990 · Genetics; (USA)

OSTI ID:6704964

Easteal, S ^[1]

---

1. Australian National Univ., Canberra (USA)

The rates of nucleotide substitution at four genes in four orders of eutherian mammals are compared in relative rate tests using marsupial orthologs for reference. There is no evidence of systematic variation in evolutionary rate among the orders. The sequences are used to reconstruct the phylogeny of the orders using maximum likelihood, parsimony and compatibility methods. A branching order of rodent then ungulate then primate and lagomorph is overwhelmingly indicated. The nodes of the nucleotide based cladograms are widely separated in relation to the total lengths of the branches. The assumption of a star phylogeny that underlies Kimura's test for molecular evolutionary rate variation is shown to be invalid for eutherian mammals. Excess variance in nucleotide or amino acid differences between mammalian orders, above that predicted by neutral theory is explained better by variation in divergence time than by variation in evolutionary rate.

• OSTI ID: 6704964
• Journal Information: Genetics; (USA), Vol. 124:1; ISSN 0016-6731
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ALBUMINS
DNA SEQUENCING
GENES
BIOLOGICAL EVOLUTION
GLOBIN
ALGORITHMS
DNA BASE TRANSITIONS
GUINEA PIGS
MAMMALS
MAN
MARSUPIALS
MUTATION FREQUENCY
RABBITS
ANIMALS
MATHEMATICAL LOGIC
ORGANIC COMPOUNDS
PRIMATES
PROTEINS
RODENTS
STRUCTURAL CHEMICAL ANALYSIS
VERTEBRATES
550400* - Genetics