''Darwinism: An Exposition of the Theory of Natural Selection with Some of Its Applications'' is an 1889 book on

evolution Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...

by Alfred Russel Wallace, the co-discoverer of evolution by

natural selection Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations. Cha ...

together with

Charles Darwin Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended ...

. This was a book Wallace wrote as a defensive response to the scientific critics of natural selection. Of all Wallace's books, it is cited by scholarly publications the most.

Synopsis

In ''Darwinism'' fifteen chapters, Alfred Russel Wallace sets out his understanding of the theory of

. He begins by defining "

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

", discussing creationism, opinion before

, and Darwin's theory. He then describes the

Malthusian Malthusianism is the idea that population growth is potentially exponential while the growth of the food supply or other resources is linear, which eventually reduces living standards to the point of triggering a population die off. This event, ...

struggle for existence, given the ability of organisms to reproduce in a world of finite resources. He explains the importance of variability within species, giving examples. He describes variation in domesticated animals and cultivated plants, and the process of artificial selection by breeders. Wallace then explains the process of natural selection acting on pre-existing variation. He lists various issues and objections to the theory. He discusses how

interspecies hybrid In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in ...

s are usually infertile, and how this can contribute to reproductive isolation. He then examines the purpose of animal coloration, including

camouflage Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the b ...

and mimicry, arguing that these are evidence of natural selection. He gives detailed examples of

warning coloration Aposematism is the advertising by an animal to potential predators that it is not worth attacking or eating. This unprofitability may consist of any defences which make the prey difficult to kill and eat, such as toxicity, venom, foul taste ...

and mimicry, discussing how these are produced by selection. Animal coloration and ornamentation that differs between the sexes are discussed, though he largely disagrees with Darwin's theory of

sexual selection Sexual selection is a mode of natural selection in which members of one biological sex choose mates of the other sex to mate with (intersexual selection), and compete with members of the same sex for access to members of the opposite sex ( ...

. Wallace then explores the co-evolution of flowers with their pollinators including insects and birds. He then describes the geographical distribution of organisms, arguing that this was created by long-distance dispersal of pioneer organisms, such as insects blown across the sea. He explains the geological evidence for evolution, the

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

record in successive layers of rock. He then examines objections to Darwinism concerning variation and heredity. Finally, he looks at how Darwinism may apply to humans. File:Darwinism 1889 page 219.jpg, Wallace discusses the purposes of herbivore coloration as danger and recognition

signals In signal processing, a signal is a function that conveys information about a phenomenon. Any quantity that can vary over space or time can be used as a signal to share messages between observers. The ''IEEE Transactions on Signal Processing'' ...

, with an illustration of

Soemmerring's gazelle Soemmerring's gazelle (''Nanger soemmerringii''), also known as the Abyssinian mohr, is a gazelle species native to the Horn of Africa (Djibouti, Eritrea, Ethiopia, Somalia and South Sudan). The species was described and given its binomen by ...

. File:Darwinism 1889 page 259 image of mimicry.jpg, Wallace discusses Batesian mimicry with a plate of a beetle that closely mimics a wasp. File:Darwinism 1889 page 320 flowers adapted for bird pollination.jpg, Wallace discusses the coevolution of flowers and pollinators, illustrating it with a bird-pollinated flower.

Analysis

In the preface to ''Darwinism'', Wallace had used the term ''pure-Darwinism'' which proposed a "greater efficacy" for natural selection. The book is notable for defending

August Weismann August Friedrich Leopold Weismann FRS (For), HonFRSE, LLD (17 January 18345 November 1914) was a German evolutionary biologist. Fellow German Ernst Mayr ranked him as the second most notable evolutionary theorist of the 19th century, after Cha ...

's theory of heredity and rejecting the

inheritance of acquired characteristics Lamarckism, also known as Lamarckian inheritance or neo-Lamarckism, is the notion that an organism can pass on to its offspring physical characteristics that the parent organism acquired through use or disuse during its lifetime. It is also calle ...

and the concept of

which Darwin gave credence to.

George Romanes George John Romanes FRS (20 May 1848 – 23 May 1894) was a Canadian-Scots evolutionary biologist and physiologist who laid the foundation of what he called comparative psychology, postulating a similarity of cognitive processes and mechanism ...

dubbed this view as "Wallaceism", noting that in contrast to Darwin, this position was advocating a "pure theory of natural selection to the exclusion of any supplementary theory."Romanes, John George. (1906)
''Darwin and After Darwin: An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions''
Volume 2. The Open Court Publishing Company. p. 12 The book is seen as laying the foundation for the

neo-Darwinian Neo-Darwinism is generally used to describe any integration of Charles Darwin's theory of evolution by natural selection with Gregor Mendel's theory of genetics. It mostly refers to evolutionary theory from either 1895 (for the combinations of Dar ...

theory of evolution. Kutschera, Ulrich; Hossfeld, Uwe. (2013). ''Alfred Russel Wallace (1823–1913): the forgotten co-founder of the Neo-Darwinian theory of biological evolution''. Theory in Biosciences 132 (4): 207–214. .

References

External links

''Darwinism: An Exposition of the Theory of Natural Selection with Some of Its Applications''
Online at

Internet Archive The Internet Archive is an American digital library with the stated mission of "universal access to all knowledge". It provides free public access to collections of digitized materials, including websites, software applications/games, music, ...

. * {{gutenberg, no=14558, name=Darwinism 1889 non-fiction books 1889 in science Books about Charles Darwin Darwinism Evolutionary biology literature

Synopsis

Analysis

References

Further reading

External links