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The history of the camel provides an example of how fossil evidence can be used to reconstruct migration and subsequent evolution. The fossil record indicates that the evolution of camelids started in North America (see figure 4e), from which, six million years ago, they migrated across the Bering Strait into Asia and then to Africa, and 3.5 ...
Professor of biology Jerry Coyne sums up biological evolution succinctly: [3]. Life on Earth evolved gradually beginning with one primitive species – perhaps a self-replicating molecule – that lived more than 3.5 billion years ago; it then branched out over time, throwing off many new and diverse species; and the mechanism for most (but not all) of evolutionary change is natural selection.
This innovation causes a major burst of animal coevolution. First freshwater pelomedusid turtles. Earliest krill. 120 Ma Oldest fossils of heterokonts, including both marine diatoms and silicoflagellates. 115 Ma First monotreme mammals. 114 Ma Earliest bees. [94] 112 Ma Xiphactinus, a large predatory fish, appears in the fossil record. 110 Ma
The history of life on Earth traces the processes by which living and extinct organisms evolved, from the earliest emergence of life to the present day. Earth formed about 4.5 billion years ago (abbreviated as Ga, for gigaannum) and evidence suggests that life emerged prior to 3.7 Ga. [1] [2] [3] The similarities among all known present-day species indicate that they have diverged through the ...
Urmetazoan: The first fossils that might represent animals appear in the 665-million-year-old rocks of the Trezona Formation of South Australia. These fossils are interpreted as being early sponges. [7] Multicellular animals may have existed from 800 Ma. Separation from the Porifera lineage.
Figure 1:In mammals, the quadrate and articular bones are small and part of the middle ear; the lower jaw consists only of dentary bone.. While living mammal species can be identified by the presence of milk-producing mammary glands in the females, other features are required when classifying fossils, because mammary glands and other soft-tissue features are not visible in fossils.
"What sets this fossil apart are the obvious differences compared to the previously known penguin remains from this period of geological history," said Dr Gerald Mayr, an ornithologist at ...
The evidence on which scientific accounts of human evolution are based comes from many fields of natural science. The main source of knowledge about the evolutionary process has traditionally been the fossil record, but since the development of genetics beginning in the 1970s, DNA analysis has come to occupy a place of comparable importance.