Sir Richard Owen KCB (Lancaster, 20 July 1804 – 18 December 1892) was an English biologist, comparative anatomist and palaeontologist.

Owen is probably best remembered today for coining the word Dinosauria (meaning "Terrible Reptile" or "Fearfully Great Reptile") and for his outspoken opposition to Charles Darwin's theory of evolution by natural selection. He agreed with Darwin that evolution occurred, but thought it was more complex than outlined in Darwin's Origin. Owen's approach to evolution can be seen as having anticipated the issues that have gained greater attention with the recent emergence of evolutionary developmental biology. He was the driving force behind the establishment, in 1881, of the British Museum (Natural History) in London. Bill Bryson argues that, "by making the Natural History Museum an institution for everyone, Owen transformed our expectations of what museums are for".

Owen was born in Lancaster and educated at Lancaster Royal Grammar School. In 1820, he was apprenticed to a local surgeon and apothecary and, in 1824, he proceeded as a medical student to the University of Edinburgh. He left the university in the following year and completed his medical course in St Bartholomew's Hospital, London, where he came under the influence of the eminent surgeon, John Abernethy.

He then contemplated the usual professional career but his bent was evidently in the direction of anatomical research. He was induced by Abernethy to accept the position of assistant to William Clift, conservator of the museum of the Royal College of Surgeons. This congenial occupation soon led him to abandon his intention of medical practice and his life henceforth was devoted to purely scientific labours. He prepared an important series of catalogues of the Hunterian Collection, in the Royal College of Surgeons and, in the course of this work, he acquired the unrivalled knowledge of comparative anatomy, which enabled him to enrich all departments of the science and especially facilitated his researches on the remains of extinct animals.

In 1836, Owen was appointed Hunterian professor, in the Royal College of Surgeons and, in 1849, he succeeded Clift as conservator. He held the latter office until 1856, when he became superintendent of the natural history department of the British Museum. He then devoted much of his energies to a great scheme for a National Museum of Natural History, which eventually resulted in the removal of the natural history collections of the British Museum to a new building at South Kensington: the British Museum (Natural History) (now the Natural History Museum). He retained office until the completion of this work, in December, 1883, when he was made a knight of the Order of the Bath. He lived quietly in retirement at Sheen Lodge, Richmond Park, until his death in 1892.

His career was tainted by accusations that he failed to give credit to the work of others and even tried to appropriate it in his own name. This came to a head in 1846, when he was awarded the Royal Medal for a paper he had written on belemnites. Owen had failed to acknowledge that the belemnite had been discovered by Chaning Pearce, an amateur biologist, four years earlier. As a result of the ensuing scandal, he was voted off the councils of the Zoological Society and the Royal Society.

Owen always tended to support orthodox men of science and the status quo. The royal family presented him with the cottage in Richmond Park and Robert Peel put him on the Civil List. In 1843, he was elected a foreign member of the Royal Swedish Academy of Sciences.

While occupied with the cataloguing of the Hunterian collection, Owen did not confine his attention to the preparations before him but also seized every opportunity to dissect fresh subjects. He was allowed to examine all animals which died in London Zoo's gardens and, when the Zoo began to publish scientific proceedings, in 1831, he was the most voluminous contributor of anatomical papers. His first notable publication, however, was his Memoir on the Pearly Nautilus (London, 1832), which was soon recognized as a classic. Henceforth, he continued to make important contributions to every department of comparative anatomy and zoology, for a period of over fifty years. In the sponges, Owen was the first to describe the now well known Venus' Flower Basket or Euplectella (1841, 1857). Among Entozoa, his most noteworthy discovery was that of Trichina spiralis (1835), the parasite infesting the muscles of man in the disease now termed trichinosis (see also Sir James Paget).

Of Brachiopoda he made very special studies, which much advanced knowledge and settled the classification, which has long been adopted. Among Mollusca, he not only described the pearly nautilus, but also Spirula (1850) and other Cephalopoda, both living and extinct and it was he who proposed the universally accepted subdivision of this class into the two orders of Dibranchiata and Tetrabranchiata (1832). The problematical Arthropod Limulus was also the subject of a special memoir by him, in 1873. Owen's technical descriptions of the Vertebrata were still more numerous and extensive than those of the invertebrate animals. His Comparative Anatomy and Physiology of Vertebrates (3 vols. London 1866 – 1868) was indeed the result of more personal research than any similar work since Georges Cuvier's Leçons d'anatomie comparée. He not only studied existing forms but also devoted great attention to the remains of extinct groups, and followed Cuvier, the pioneer of vertebrate paleontology. Early in his career, he made exhaustive studies of teeth of existing and extinct animals and published his profusely illustrated work on Odontography (1840 – 1845). He discovered and described the remarkably complex structure of the teeth of the extinct animals which he named Labyrinthodonts. Among his writings on fish, his memoir on the African lungfish, which he named Protopterus, laid the foundations for the recognition of the Dipnoi by Johannes Müller. He also later pointed out the serial connection between the teleostean and ganoid fishes, grouping them in one sub-class, the Teleostomi.

Most of his work on reptiles related to the skeletons of extinct forms and his chief memoirs, on British specimens, were reprinted in a connected series in his History of British Fossil Reptiles (4 vols. London 1849 – 1884). He published the first important general account of the great group of Mesozoic land reptiles, and he coined the name Dinosauria from Greek δεινός (deinos) "terrible, powerful, wondrous" + σαῦρος (sauros) "lizard". Owen used 3 genera to define the dinosaurs: the carnivorous Megalosaurus, the herviborous Iguanodon and armoured Hylaeosaurus. He also first recognized the curious early Mesozoic land reptiles, with affinities both to amphibians and mammals, which he termed Anomodontia (the mammal like reptiles, Therapsida). Most of these were obtained from South Africa, beginning in 1845 (Dicynodon) and eventually furnished materials for his Catalogue of the Fossil Reptilia of South Africa, issued by the British Museum, in 1876. Among his writings on birds, his classical memoir on the kiwi (1840 – 1846), a long series of papers on the extinct dinornithidae of New Zealand, other memoirs on aptornis, the takahe, the dodo and the Great Auk, may be especially mentioned. His monograph on Archaeopteryx (1863), the long tailed, toothed bird from the Bavarian lithographic stone, is also an epoch making work.

With Benjamin Waterhouse Hawkins, Owen helped create the first life size sculptures depicting dinosaurs as he thought they may have appeared. Some models were initially created for the Great Exhibition of 1851, but 33 were eventually produced when the Crystal Palace was relocated to Sydenham, in South London. Owen famously hosted a dinner for 21 prominent men of science inside the hollow concrete Iguanodon on New Year's Eve 1853. However, in 1849, a few years before his death in 1852, Gideon Mantell had realised that Iguanodon, of which he was the discoverer, was not a heavy, pachyderm like animal, as Owen was putting forward, but had slender forelimbs; his death left him unable to participate in the creation of the Crystal Palace dinosaur sculptures, and so Owen's vision of dinosaurs became that seen by the public. He had nearly two dozen lifesize sculptures of various prehistoric animals built out of concrete sculpted over a steel and brick framework; two Iguanodon, one standing and one resting on its belly, were included.

Owen was granted right of first refusal on any freshly dead animal at the London Zoo. His wife once arrived home to find the carcass of a newly deceased rhinoceros in her front hallway.

With regard to living mammals, the more striking of Owen's contributions relate to themonotremes, marsupials and the anthropoid apes. He was also the first to recognize and name the two natural groups of typical Ungulate, the odd toed (Perissodactyla) and the even toed (Artiodactyla), while describing some fossil remains, in 1848. Most of his writings on mammals, however, deal with extinct forms, to which his attention seems to have been first directed by the remarkable fossils collected by Charles Darwin, in South America. Toxodon, from the pampas, was then described and gave the earliest clear evidence of an extinct generalized hoof animal, a pachyderm with affinities to the Rodentia, Edentata and herbivorous Cetacea. Owen's interest in South American extinct mammals then led to the recognition of the giant armadillo, which he named Glyptodon (1839) and to classic memoirs on the giant ground sloths, Mylodon (1842) and Megatherium (1860), besides other important contributions.

At the same time, Sir Thomas Mitchell's discovery of fossil bones, in New South Wales, provided material for the first of Owen's long series of papers on the extinct mammals of Australia, which were eventually reprinted in book form in 1877. He discovered Diprotodon and Thylacoleo, besides extinct kangaroos and wombats, of gigantic size. While occupied with so much material from abroad, Owen was also busily collecting facts for an exhaustive work on similar fossils from the British Isles and, in 1844 - 1846, he published his History of British Fossil Mammals and Birds, which was followed by many later memoirs, notably his Monograph of the Fossil Mammalia of the Mesozoic Formations (Palaeont. Soc., 1871). One of his latest publications was a little work entitled Antiquity of Man as deduced from the Discovery of a Human Skeleton during Excavations of the Docks at Tilbury (London, 1884).

Following the voyage of the Beagle, Darwin had at his disposal a considerable collection of specimens and, on 29 October 1836, he was introduced by Charles Lyell to Owen, who agreed to work on fossil bones collected in South America. Owen's subsequent revelations, that the extinct giant creatures were rodents and sloths, showed that they were related to current species in the same locality, rather than being relatives of similarly sized creatures in Africa, as Darwin had originally thought. This was one of the many influences which led Darwin to later formulate his own ideas on the concept of natural selection.

At this time, Owen talked of his theories, influenced by Johannes Peter Müller, that living matter had an "organising energy", a life force that directed the growth of tissues and also determined the lifespan of the individual and of the species. Darwin was reticent about his own thoughts, understandably, when, on 19 December 1838, as secretary of the Geological Society of London, he saw Owen and his allies ridicule the Lamarckian 'heresy' of Darwin's old tutor, Robert Edmund Grant. In 1841, when the recently married Darwin was ill, Owen was one of the few scientific friends to visit; however, Owen's opposition to any hint of transmutation made Darwin keep quiet about his hypothesis.

Sometime during the 1840s Owen came to the conclusion that species arise as the result of some sort of evolutionary process. He believed that there was a total of six possible mechanisms: parthenogenesis, prolonged development, premature birth, congenital malformations, Lamarckian atrophy, Lamarckian hypertrophy and transmutation, of which he thought transmutation was the least likely. The historian of science Evelleen Richards has argued that Owen was likely sympathetic to developmental theories of evolution, but backed away from publicly proclaiming them after the criticism Robert Chambers got for his evolutionary book in 1844, and that Owen got for his evolutionary remarks in his Nature of the Limbs in 1849. At the end of On the Nature of Limbs Owen had suggested that humans ultimately evolved from fish as the result of natural laws, which resulted in him getting criticized in the Manchester Spectator for denying species like humans were created by God.

During the development of Darwin's theory, his investigation of barnacles showed, in 1849, how their segmentation related to other crustaceans, showing how they had diverged from their relatives. To both Darwin and Owen such "homologies" in comparative anatomy was evidence of descent. Owen demonstrated fossil evidence of an evolutionary sequence of horses, as supporting his idea of development from archetypes in "ordained continuous becoming" and, in 1854, gave a British Association talk on the impossibility of bestial apes, such as the recently discovered gorilla, standing erect and being transmuted into men, but Owen did not rule out the possibility that humans evolved from other extinct animals by evolutionary mechanisms other than transmutation. Working class militants were trumpeting man's monkey origins, and in 1861 Karl Marx wrote: "Darwin's work is most important and suits my purpose in that it provides a basis in natural science for the historical class struggle." To crush these ideas, Owen, as President elect of the Royal Association, announced his authoritative anatomical studies of primate brains, claiming that the human brain had structures that apes brains did not, and that therefore humans were a separate sub-class. Owen's main argument was that humans have much larger brains for their body size than other mammals including the great apes. Darwin wrote that "I cannot swallow Man [being that] distinct from a Chimpanzee". The combative Thomas Henry Huxley used his March 1858 Royal Institution lecture to deny Owen's claim and affirmed that structurally, gorillas are as close to humans as they are to baboons. He believed that the "mental & moral faculties are essentially... the same kind in animals & ourselves". This was a clear denial of Owen's claim for human uniqueness, given at the same venue.

On the publication of Darwin's theory, in On The Origin of Species, he sent a complimentary copy to Owen, saying "it will seem 'an abomination'". Owen was the first to respond, courteously claiming that he had long believed that "existing influences" were responsible for the "ordained" birth of species. Darwin now had long talks with him and Owen said that the book offered the best explanation "ever published of the manner of formation of species", although he still had the gravest doubts that transmutation would bestialize man. It appears that Darwin had assured Owen that he was looking at everything as resulting from designed laws, which Owen interpreted as showing a shared belief in "Creative Power".

As head of the Natural History Collections at the British Museum, Owen received numerous inquiries and complaints about the Origin. His own views remained unknown: when emphasising to a Parliamentary committee the need for a new Natural History museum, he pointed out that "The whole intellectual world this year has been excited by a book on the origin of species; and what is the consequence? Visitors come to the British Museum, and they say, "Let us see all these varieties of pigeons: where is the tumbler, where is the pouter?" and I am obliged with shame to say, I can show you none of them".... As to showing you the varieties of those species, or of any of those phenomena that would aid one in getting at that mystery of mysteries, the origin of species, our space does not permit; but surely there ought to be a space somewhere, and, if not in the British Museum, where is it to be obtained?"

However, Huxley's attacks were making their mark. In April 1860 the Edinburgh Review included Owen's anonymous review of the Origin. In it Owen showed his anger at what he saw as Darwin's caricature of the creationist position, and his ignoring Owen's "axiom of the continuous operation of the ordained becoming of living things". As well as attacking Darwin's "disciples", Hooker and Huxley, for their "short sighted adherence", he thought that the book symbolised the sort of "abuse of science... to which a neighbouring nation, some seventy years since, owed its temporary degradation" in a reference to the French Revolution. Darwin thought it "Spiteful, extremely malignant, clever, and... damaging" and later commented that "The Londoners say he is mad with envy because my book is so talked about. It is painful to be hated in the intense degree with which Owen hates me."

During the reaction to Darwin's theory, Huxley's arguments with Owen continued. Owen tried to smear Huxley, by portraying him as an "advocate of man's origins from a transmuted ape" and one of his contributions to the Athenaeum was titled "Ape Origin of Man as Tested by the Brain". In 1862 (and on other occasions) Huxley took the opportunity to arrange demonstrations of ape brain anatomy (e.g. at the BA meeting, where William Flower performed the dissection). Visual evidence of the supposedly missing structures (posterior cornu and hippocampus minor) was used, in effect, to indict Owen for perjury. Owen had argued that the absence of those structures in apes were connected with the lesser size to which the ape brains grew, but he then conceded that a poorly developed version might be construed as present without preventing him from arguing that brain size was still the major way of distinguishing apes and humans. Huxley's campaign ran over two years and was devastatingly successful at persuading the overall scientific community, with each "slaying" being followed by a recruiting drive for the Darwinian cause. The spite lingered. While Owen had argued that humans were distinct from apes by virtue of having large brains, Huxley claimed that racial diversity blurred any such distinction. In his paper criticizing Owen, Huxley directly states: "if we place A, the European brain, B, the Bosjesman brain, and C, the orang brain, in a series, the differences between A and B, so far as they have been ascertained, are of the same nature as the chief of those between B and C". Owen countered Huxley by saying the brains of all human races were really of similar size and intellectual ability, and that the fact that humans had brains that were twice the size of large apes like male gorillas, even though humans had much smaller bodies, made humans distinguishable. When Huxley joined the Zoological Society Council, in 1861, Owen left and, in the following year, Huxley moved to stop Owen from being elected to the Royal Society Council, accusing him "of wilful & deliberate falsehood".

In January 1863, Owen bought the Archaeopteryx fossil for the British Museum. It fulfilled Darwin's prediction, that a proto-bird with unfused wing fingers would be found, although Owen described it unequivocally as a bird.

The feuding between Owen and Darwin's supporters continued. In 1871, Owen was found to be involved in a threat to end government funding of Joseph Dalton Hooker's botanical collection, at Kew, possibly trying to bring it under his British Museum. Darwin commented that "I used to be ashamed of hating him so much, but now I will carefully cherish my hatred & contempt to the last days of my life".

Owen's detailed memoirs and descriptions require laborious attention in reading, on account of their complex terminology and ambiguous modes of expression. The fact that very little of his terminology has found universal favour causes them to be more generally neglected than they otherwise would be. At the same time, it must be remembered that he was a pioneer in concise anatomical nomenclature and, so far at least as the vertebrate skeleton is concerned, his terms were based on a carefully reasoned philosophical scheme, which first clearly distinguished between the now familiar phenomena of analogy and homology.

Owen's theory of the Archetype and Homologies of the Vertebrate Skeleton (1848), subsequently illustrated also by his little work On the Nature of Limbs (1849), regarded the vertebrate frame as consisting of a series of fundamentally identical segments, each modified according to its position and functions. Much of it was fanciful and failed when tested by the facts of embryology, which Owen systematically ignored, throughout his work. However, though an imperfect and distorted view of certain great truths, it possessed a distinct value at the time of its conception.

To the discussion of the deeper problems of biological philosophy, he made scarcely any direct and definite contributions. His generalities rarely extended beyond strict comparative anatomy, the phenomena of adaptation to function and the facts of geographical or geological distribution. His lecture on virgin reproduction or parthenogenesis, however, published in 1849, contained the essence of the germ plasm theory, elaborated later by August Weismann and he made several vague statements concerning the geological succession of genera and species of animals and their possible derivation one from another. He referred, especially, to the changes exhibited by the successive forerunners of the crocodiles (1884) and horses (1868) but it has never become clear how much of the modern doctrines of organic evolution he admitted. He contented himself with the bare remark that "the inductive demonstration of the nature and mode of operation of the laws governing life would henceforth be the great aim of the philosophical naturalist."

He was the first director in Natural History Museum in London and his statue was in the main hall there until 2009, when it was replaced with a statue of Darwin.

"Owen: the most distinguished vertebrate zoologist and palaeontologist... but a most deceitful and odious man." Richard Broke Freeman (Charles Darwin: a Companion. Dawson 1978)

"No one fact tells so strongly against Owen... as that he has never reared one pupil or follower." Charles Darwin to Asa Gray, 1860. (More Letters of C.D p153)

Owen has been described by some as a malicious, dishonest and hateful individual. He has been described in one biography as being a "social experimenter with a penchant for sadism. Addicted to controversy and driven by arrogance and jealousy". Deborah Cadbury stated that Owen possessed an "almost fanatical egoism with a callous delight in savaging his critics." Indeed, an Oxford University professor once described Owen as "a damned liar. He lied for God and for malice". Gideon Mantell claimed it was "a pity a man so talented should be so dastardly and envious".

Owen famously credited himself and Georges Cuvier with the discovery of the Iguanodon, completely excluding any credit for the original discoverer of the dinosaur, Gideon Mantell. This was not the first or last time Owen would deliberately claim a discovery as his own, when in fact it was not. It has also been suggested by some authors, including Bill Bryson in A Short History of Nearly Everything, that Owen even used his influence in the Royal Society to ensure that many of Mantell’s research papers were never published. Owen was finally dismissed from the Royal Society's Zoological Council for plagiarism.

When Mantell suffered an accident that left him permanently crippled, Owen exploited the opportunity by renaming several dinosaurs which had already been named by Mantell, even having the audacity to claim credit for their discovery himself. When Mantell finally died in 1852, an obituary carrying no byline derided Mantell as little more than a mediocre scientist, who brought forth few notable contributions. The obituary’s authorship was universally attributed to Owen by every geologist. The president of the Geological society claimed that it "bespeaks of the lamentable coldness of the heart of the writer". Owen was subsequently denied the presidency of the society for his repeated and pointed antagonism towards Gideon Mantell.

Even more extraordinary was the way Owen ignored the genuine scientific content of Mantell's work. For example, despite the paucity of finds Mantell had worked out that some dinosaurs were bipedal, including Iguanodon. This remarkable insight was totally ignored by Owen, whose instructions for the Crystal Palace models by Waterhouse Hawkins portrayed Iguanodon as grossly overweight and quadrupedal, with its misidentified thumb on its nose. Mantell did not live to witness the discovery in 1878 of articulated skeletons in a Belgium coal mine that showed Iguanodon was mostly bipedal (and in that stance could use its thumb for defence). Owen made no comment or retraction; he never did on any errors he made. Moreover, since the earliest known dinosaurs were bipedal, Mantell's idea was indeed perspicacious.

Despite originally starting out on good terms with Darwin, Owen was highly critical of the Origin in large part because Darwin did not refer much to the previous scientific theories of evolution that had been proposed by people like Chambers and himself, and instead compared the theory of evolution by natural selection with the unscientific theory in the Bible.

Another reason for his criticism of the Origin, some historians claim, was that Owen felt upstaged by Darwin and supporters such as Huxley, and his judgment was clouded by jealousy. Owen in Darwin's opinion was "Spiteful, extremely malignant, clever; the Londoners say he is mad with envy because my book is so talked about". "It is painful to be hated in the intense degree with which Owen hates me". Owen also resorted to the same subterfuge he used against Mantell, writing another anonymous article in the Edinburgh Review in April 1860. In the article, Owen was critical of Darwin for not offering many new observations, and heaped praise (in the third person) upon himself, while being careful not to associate any particular comment with his own name. Owen did praise, however, the Origin's description of Darwin's work on insect behavior and pigeon breeding as "real gems".

Owen was also a party to the threat to end government funding of the Royal Botanic Gardens, Kew botanical collection (Attacks on Hooker and on Kew), orchestrated by Acton Smee Ayrton:

"There is no doubt that rivalry resulted between the British Museum, where there was the very important Herbarium of the Department of Botany, and Kew. The rivalry at times became extremely personal, especially between Joseph Hooker and Owen… At the root was Owen’s feeling that Kew should be subordinate to the British Museum (and to Owen) and should not be allowed to develop as an independent scientific institution with the advantage of a great botanic garden."

It has been suggested by some authors that the portrayal of Owen as a vindictive and treacherous man was fostered and encouraged by his rivals (particularly Darwin, Hooker and Huxley) and may be somewhat undeserved. In the first part of his career he was regarded rightly as one of the great scientific figures of the age. In the second part of his career his reputation slipped. This was not solely due to his underhanded dealings with colleagues; it was also due to the serious errors of scientific judgement which were discovered and publicized. A fine example was his decision to classify man in a separate sub-class of the Mammalia. In this Owen had no supporters at all. Also, his unwillingness to come off the fence concerning evolution became increasingly damaging to his reputation as time went on. Owen continued working after his official retirement at the age of 79, but he never recovered the good opinions he had garnered in his younger days.