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The last common ancestor between humans and other apes possibly had a similar method of locomotion. 12-8 Ma The clade currently represented by humans and the genus Pan (chimpanzees and bonobos) splits from the ancestors of the gorillas between c. 12 to 8 Ma. [31] 8-6 Ma Sahelanthropus tchadensis
The Carboniferous rainforest collapse occurs, causing a minor extinction event, as well as paving the way for amniotes to become dominant over amphibians and seed plants over ferns and lycophytes. First diapsid reptiles (e.g. Petrolacosaurus). 280 Ma Earliest beetles, seed plants and conifers diversify while lepidodendrids and sphenopsids decrease.
About ten thousand years ago, humans in the Fertile Crescent of the Middle East develop agriculture. Plant domestication begins with cultivation of Neolithic founder crops. This process of food production, coupled later with the domestication of animals caused a massive increase in human population that has continued to the present.
Edward Hitchcock's fold-out paleontological chart in his 1840 Elementary Geology. Although tree-like diagrams have long been used to organise knowledge, and although branching diagrams known as claves ("keys") were omnipresent in eighteenth-century natural history, it appears that the earliest tree diagram of natural order was the 1801 "Arbre botanique" (Botanical Tree) of the French ...
The Bode phase plot is the graph of the phase, commonly expressed in degrees, of the transfer function ((=)) as a function of . The phase is plotted on the same logarithmic ω {\displaystyle \omega } -axis as the magnitude plot, but the value for the phase is plotted on a linear vertical axis.
In some plants the gametophyte is not only small-sized but also short-lived; in other plants and many algae, the gametophyte is the "dominant" stage of the life cycle. [19] Haplodiplonts are: In archaeplastidans: red algae (which have two sporophyte generations), some green algae (e.g., Ulva), land plants [8] [9] In stramenopiles: most brown ...
Evolution is the change in the heritable characteristics of biological populations over successive generations. [1] [2] It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certain characteristics becoming more or less common within a population over successive generations. [3]
In plants both phases are multicellular: the haploid sexual phase – the gametophyte – alternates with a diploid asexual phase – the sporophyte. A mature sporophyte produces haploid spores by meiosis, a process which reduces the number of chromosomes to half, from two sets to one. The resulting haploid spores germinate and grow into ...