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Charles Darwin (1809–1882) used the metaphor of a "tree of life" to conceptualise his theory of evolution. In On the Origin of Species (1859) he presented an abstract diagram of a portion of a larger timetree for species of an unnamed large genus (see figure). On the horizontal base line hypothetical species within this genus are labelled A ...
A spindle diagram, showing the evolution of the vertebrates at class level, width of spindles indicating number of families. Spindle diagrams are often used in evolutionary taxonomy. A spindle diagram, or bubble diagram, is often called a romerogram, after its popularisation by the American palaeontologist Alfred Romer. [17]
Beginning of animal evolution. [54] [55] 720–630 Ma Possible global glaciation [56] [57] which increased the atmospheric oxygen and decreased carbon dioxide, and was either caused by land plant evolution [58] or resulted in it. [59] Opinion is divided on whether it increased or decreased biodiversity or the rate of evolution. [60] [61] [62 ...
Cladogram – Diagram used to show relations among groups of organisms with common origins; Phylogenetic tree – Branching diagram of evolutionary relationships between organisms; Phylogenetics – Study of evolutionary relationships between organisms Cladistics – Method of biological systematics in evolutionary biology
The evolution of eukaryotes, and possibly sex, is thought to be related to the GOE, as it probably pressured two or three lineages of prokaryotes (including an aerobe one, which later became mitochondria) to depend on each other, leading to endosymbiosis. Early eukaryotes lost their cell walls and outer membranes.
Humans determine which animal or plant will reproduce and which of the offspring will survive; thus, they determine which genes will be passed on to future generations. The process of artificial selection has had a significant impact on the evolution of domestic animals. For example, people have produced different types of dogs by controlled ...
This tree diagram, used to show the divergence of species, is the only illustration in the Origin of Species. Darwin proposes sexual selection, driven by competition between males for mates, to explain sexually dimorphic features such as lion manes, deer antlers, peacock tails, bird songs, and the bright plumage of some male birds. [129]
The evolution and distribution of the various taxa through time is commonly shown as a spindle diagram (often called a Romerogram after the American palaeontologist Alfred Romer) where various spindles branch off from each other, with each spindle representing a taxon. The width of the spindles are meant to imply the abundance (often number of ...