Search results
Results from the WOW.Com Content Network
With only a handful of species surviving today, the Nautiloids flourished during the early Paleozoic era, from the Late Cambrian, where they constituted the main predatory animals. [71] Haikouichthys , a jawless fish , is popularized as one of the earliest fishes and probably a basal chordate or a basal craniate . [ 72 ]
A so-called "cathedral" mound produced by a termite colony. Structures built by non-human animals, often called animal architecture, [1] are common in many species. Examples of animal structures include termite mounds, ant hills, wasp and beehives, burrow complexes, beaver dams, elaborate nests of birds, and webs of spiders.
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 ...
This made no sense under doctrines of independent creation of species, as even Richard Owen had admitted, but the "explanation is manifest on the theory of the natural selection of successive slight modifications" showing common descent. [169] He notes that animals of the same class often have extremely similar embryos. Darwin discusses ...
Evolutionary thought, the recognition that species change over time and the perceived understanding of how such processes work, has roots in antiquity. With the beginnings of modern biological taxonomy in the late 17th century, two opposed ideas influenced Western biological thinking: essentialism, the belief that every species has essential characteristics that are unalterable, a concept ...
Darwin carefully observed the outcomes of artificial selection in animals and plants to form many of his arguments in support of natural selection. [67] Much of his book On the Origin of Species was based on these observations of the many varieties of domestic pigeons arising from artificial selection. Darwin proposed that if humans could ...
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 ...
Starting with Charles Darwin, many scientists have conducted experiments and made observations that have shown that the types of animals and plants found, and not found, on such islands are consistent with the theory that these islands were colonized accidentally by plants and animals that were able to reach them. Such accidental colonization ...