Clark, Wilfrid Edward Le Gros
CLARK, WILFRID EDWARD LE GROS
(b. Hemel Hempstead, Hertfordshire, United Kingdom, 5 June 1895;
d. Barton Bradstock, Dorset, United Kingdom, 28 June 1971), comparative anatomy,primatology, paleopr imatology, paleoanthropology, neuroanatomy.
Clark’s knowledge of anatomy covered a wide area from fossil skeletal remains of nonhuman and hominid primates to the comparative structural and functional anatomy of organ systems throughout the primate order. A particular interest was the brain: His experimental anatomy that contributed to insights into the connections of the thalamus, the hypothalamus, and the sensory input to the brain was fundamental to the development of neuroanatomy. In fact, Clark had a profound influence on the teaching of anatomy as he moved from a topographical learning by heart to an emphasis on the connection between structure and function. In the field of paleoanthropology, Clark was a key figure in uncovering the Piltdown forgery and in establishing the australopithecines as hominids.
In general, Clark’s work is of interest to the historian as it spans one of the major transitions in paleoanthropology, when it was updated with the methodological and conceptual changes that had taken place in biology in the course of the evolutionary synthesis, to form “a new physical anthropology”(after Sherwood L. Washburn). Clark’s work is also a pleasure to study due to his clarity and economy of language. This advantage has been attributed to a speech impediment that as a young man threatened his plan of an academic career. His effort in overcoming the handicap was of such a nature that it turned his oratory and writing skills into an example for others. His lucidity in style may be enjoyed in the History of Primates: An Introduction to the Study of Fossil Man (1949), which was addressed to a more general public.
Education and Early Anatomical Work . Clark spent his first nine years in Newnham, Gloucestershire, but after the death of his mother, his father accepted the rectory of Washfield, near Triverton, in Devon. He attended a preparatory school at Malvern Wells and entered Blundell’s School in Triverton in 1910. He was the youngest of three sons of the Reverend Travers Clark, who intended Wilfrid to follow in the footsteps of his grandfathers, both of whom had been at St. Thomas’s Hospital. Indeed, Clark entered St. Thomas’s Hospital Medical School (1912) on an entrance scholarship. He enjoyed a close relationship and shared many interests with his brothers. It was after one of their frequent walking and nature observation tours in Dartmoor (his father had retired at Teignmouth) on 4 August 1914 that they heard of the declaration of war. After qualifying at Medical School in 1917, Clark entered the Royal Army Medical Corps. Serving in France until the end of World War I, he returned to St. Thomas’s Hospital to study for his surgical qualifications in 1919.
A turning point came in 1920 when he left for northwestern Borneo as principal medical officer to Sarawak for three years, where his elder brother was minister of state. In fact, his services as physician and surgeon were valued so highly that he was tattooed on the shoulders with the insignia of the Sea Dyaks of Borneo. There, Clark also followed the advice of the influential anatomist Grafton Elliot Smith and took the opportunity to study the tree-shrews (Tupaia) and tarsiers (Tarsius) of the region, on which his early work was centered (e.g., Clark, 1924a, 1924b). He returned to England and, in 1923, accepted the post as reader of anatomy at St. Bartholomew’s Hospital, where he was named professor in 1927.
His continued work on the tree-shrew and tarsier led him to accept Elliot Smith’s view that the modern tree-shrew resembled most the earliest primates that first differentiated from the mammalian/insectivore stem. They had to be considered primates, not insectivores. This theory, based on dissections, was published in Early Forerunners of Man: A Morphological Study of the Evolutionary Origin of the Primates(1934), dedicated to Elliot Smith, who had been a great inspiration to him. The book reviewed the different anatomical body systems for the information they provided on the phylogeny of the primates. After having again moved to St. Thomas’s as professor of anatomy in 1930, Clark finally left for Oxford University’s chair of anatomy in 1934. The following year, his work on primate evolution secured him the election to a Fellowship of the Royal Society.
Australopithecus . From the mid-1920s onwards, australopithecine remains were discovered in South Africa and subsequently East Africa. Although the australopithecine discoverers came to regard the new creatures as missing links between apes and humans, the anthropological communities in general judged them to be fossil apes with no particular relation to humans. This judgment was motivated mainly by three factors: brain expansion was considered to have been the hominid specialization that led away from the pongid line; Asia, rather than Africa, was favored as the cradle of humankind; and the persistence of non-Darwinian mechanisms of evolution. The small-brained but bipedal australopithecines from Africa thus did not fit the expected pattern, and their morphological similarities to hominids were explained by parallel evolution rather than close kinship.
Prior to the update of paleoanthropology through the evolutionary synthesis, it was commonplace to accept mechanisms other than natural selection and adaptation, such as the inheritance of acquired characters and ortho-genesis, for hominid evolution. The typological approach dominant at that time also meant that rather than recognizing intraspecific variation in the often fragmentary fossil record, there was a tendency to describe every new fossil hominid as a separate species, if not genus.
One obstacle to the acceptance of australopithecines as hominids was that, up to that point, the oldest hominid fossils had been discovered in Asia. Another was the so-called Piltdown Man. During the years of 1911 and 1912, several cranial fragments and the right half of a mandible containing molar teeth were reportedly unearthed by Charles Dawson and others in a gravel pit at Piltdown in Sussex, England. While the mandible was ape-like, the braincase was modern looking. In contrast, Pithecanthropus erectus(later Homo erectus) from Java, consisting of a femur, calvarium, and some teeth, discovered by the Dutch physician Eugène Dubois at Trinil in 1891–1892, though suggesting bipedal locomotion, had a small cranial capacity.
Piltdown was thus welcome support for the widespread assumption that the expansion of the brain had preceded the acquisition of a fully upright posture in the course of human evolution. The fact that already at the Pliocene-Pleistocene boundary there had been a human type of an essentially modern skull size put into question the ancestral status of Pithecanthropus and other early hominid remains, which seemed to date from about the same period, but were less modern in brain anatomy. Once the australopithecines came to be viewed as hominids and even as ancestral to modern humans, they catalyzed the turn of focus from Asia to Africa as the cradle of humankind and made the Piltdown assemblage look odder than ever. The eventual unmasking of the Pilt-down forgery removed the final conceptual stronghold of the brain-first theory.
Following the general trend, in the Early Forerunners of Man Clark discussed the australopithecines as fossil remains of African anthropoid apes. He cautioned that parallel evolution had been a central mechanism in the evolutionary radiation of the primates, thus the separation of the hominid from the anthropoid line might have taken place earlier than an estimate based on comparative anatomy alone would suggest. Here, Clark positioned himself against evolution by selection among random variations and followed the American paleontologist Henry Fairfield Osborn in his assumption of evolutionary trends programmed into the germ plasm that would lead the evolution of related forms into similar directions. Even at the risk of vitalism, Clark thought such orthogenesis preferable over pure contingency as a shaper of primate evolution. Parallel evolution could explain the human-like traits of Australopithecus without inferring that australopithecines were hominids.
During World War II, Robert Broom, who with Raymond Dart was the main discoverer of australopithecine remains, started a voluminous correspondence with Clark despite the slow mail service. Clark, whose main research was at that time connected to the war effort notwithstanding his pacifist principles (muscle and nerve regeneration, ergonomics), received information on all the latest discoveries and casts of the man-ape (or ape-man, as Clark would reckon later) material, to the effect that he became Broom’s mouthpiece at British scientific meetings. With each new fragment of australopithecines discovered, insights into their morphology grew, so that eventually their affinities to humans in dentition, way of locomotion, and precision in hand movement could no longer be doubted or explained by parallel evolution.
Therefore, at the first Pan-African Congress on Prehistory in Nairobi in 1947, Clark presented the insights gained from his studies of the australopithecine material during a short South Africa visit: “The general conclusion was reached that the Australopithecinae must at least be regarded as having a fairly close relationship to the ancestral stock which gave rise to the Hominidae” (1947a, p. 101). Even more significantly, Clark carried out a detailed analysis of australopithecine teeth compared with pongid and hominid dentition, which was later drawn on by Donald Johanson and Timothy White in their reorganization of the African fossil record from Ethiopia and Laetoli (Clark, 1950). Australopithecines were to be regarded as hominids, and Clark was aware of the fact that the taxonomist and evolutionary synthesist Ernst Mayr (1950) had even gone as far as including them in the genus Homo. As a happy ending to the australopithecine story, Broom’s book Finding the Missing Link appeared in 1950, and Clark’s The Fossil Evidence for Human Evolution: An Introduction to the Study of Paleoanthropology in 1955. Both advocated the important role of the australopithecines in hominid evolution.
The New Physical Anthropology . Clark’s book represented a review of the current status of fossil evidence, and it was required reading for a generation of students in physical anthropology. The Fossil Evidence for Human Evolution is a remarkable work in more than one way. It proves the author’s deep and wide knowledge of the fossil record, history of discoveries, related literature, and associated controversies, as well as the various methods applied to their analysis. It may also be valued, as has indeed been expressed by many reviewers, for its dispassionate and cautious stance. Clark provided the different views held by anthropologists with regard to questions of taxonomy and phylogeny, and while he emphasized the reasons for his own judgments, these were always presented as working hypotheses rather than definitive claims.
Clark’s book was indicative of changes that had taken place in paleoanthropology with respect to other areas than the australopithecine question. Besides attributing less importance to evolutionary parallelism, it strongly relied on the paleontologist George Gaylord Simpson, who rewrote human paleontology on the basis of a biological concept of species and the new systematics. Simpson and others interpreted the hominid fossil record within the framework of variation within populations and possible reproductive isolation between groups (polymorphic species as reproductive, ecological, and genetical units). The existence of taxonomic entities established on these criteria could then be explained by the mechanisms of natural selection, adaptation, and genetic drift. Clark stressed the need for an appreciation of modern evolutionary and genetic concepts and the significance of functional anatomical studies. His book clearly represented a much-needed introduction to human evolution that recognized fully the advances made in modern biology. He also followed the trend of reducing the number of taxa and including more variation within each taxon.
The Fossil Evidence for Human Evolution might also be symptomatic of post–World War II paleoanthropology in that Clark took a clear stance against views according to which the modern human “races” had long independent histories and had evolved separately since the beginning of the Pleistocene. Correspondingly, he rejected the attempt to recognize in some fossils of supposedly Pleistocene age the precedents of existing races:
No fossil skeleton that is indisputably older than the end of the Pleistocene has yet been discovered which can be certainly identified asof Negroid or Mongolian stock, and the skulls of Australoid type found at Wadjak, Talgai, Cohuna, and Aitape have all been assigned a Pleistocene date on evidence which is regarded by some authorities as geologically inadequate. (1964, p. 55)
If paleoanthropology was still a source of moral lessons, these differed markedly from their prewar counterparts, as might be glimpsed from History of the Primates, which ends with a warning to the general reader:
If Man has gained his intellectual dominance over his fellow creatures by concentrating his evolutionary energies on the development of his brain, it remains to be seen whether he can now maintain his position by contriving a method of living in orderly relations with members of his own species. If he fails to do so, he may yet follow the example of many other groups of animals which have achieved atemporary ascendancy by an exaggerated development of some particular structural mechanism. He may become extinct. (1950a, p. 112)
In The Fossil Evidence for Human Evolution, Clark devoted a chapter to the dangers and fallacies of the quantitative assessment of taxonomic relationships (such as relying on too few measurements, using characters that are irrelevant for the establishment of taxonomic relationships, treating characters in isolation rather than in combination, or simply wrong statistics). His reliance on overall morphological patterns for the allocation of fossils to taxa brought him into opposition with South-African-born Solly Zuckerman’s statistical approach to taxonomy. Unlike Zuckerman, who had spent a decade in Clark’s Department of Anatomy at Oxford University (1934–1945), Clark was convinced that the interrelationship of anatomical features and their interpretation in functional terms was the most robust method to arrive at taxonomic relationships.
The work of Zuckerman, who launched one of the last attacks against the australopithecines’ hominid status, was nonetheless also illustrative of a new paleoanthropology. After his move from Oxford to Birmingham University, Zuckerman was involved in a research program for the application of biometry to paleoanthropology. With regard to the australopithecines, Zuckerman’s analysis of teeth indicated a close relationship to chimpanzees, which turned the australopithecine controversy into a battle between the descriptive and the statistical method. Zuckerman was in favor of biometry, genetics, and natural selection, while Broom had no regard for any of the three. Clark agreed with Broom that the biometry applied to Australopithecus teeth was meaningless (see also Clark, 1950). Ironically, the controversy ended when biometricians came to Broom’s support by finding fault with Zuckerman’s figures; apparently he had forgotten to divide his numbers by the square root of two (Ashton and Zuckerman, 1950, 1951).
Besides his role in establishing the australopithecines as hominids, Clark also worked and published extensively on the fossil primate remains from East Africa that were made famous by Louis S. B. Leakey (e.g., Clark and Leakey, 1950; Clark and Thomas, 1952). Furthermore, he took part in the dismantling of the Piltdown forgery mentioned earlier. Despite their anthropoid morphology, the Piltdown teeth’s wear was more characteristic of human beings. However, Clark’s analysis brought to light that the molar teeth in the mandible and the canine had undergone postmortem artificial abrasion so as to give the impression of natural attrition during a hominid way of life. Clark concluded that teeth and jaw were in fact those of an orangutan. In combination with Kenneth Page Oakley’s evidence through chemical analysis of fluorine and nitrogen content that showed that the jaw and cranium were not of the same age and not as old as claimed, and with the insight that the bones had been artificially colored, the Piltdown chimera was finally removed from the fossil record (Clark, Weiner, and Oakley, 1953; Weiner, Clark, Oakley, et al., 1955).
In 1959, the new anatomy department Clark had begun to create at Oxford was finally opened, and Clark published The Antecedents of Man: An Introduction to the Evolution of the Primates. It was based on the Munro lectures he had delivered at the University of Edinburgh in 1953 on the subject of the paleontology of the primates and the problem of human ancestry. It was intended to replace The Early Forerunners of Man, which had been out of print for a long time, among other things because stocks had been destroyed in the bombing raids of World War II. The new encompassing work covered primate comparative anatomy, comparative embryology, paleontology, and cranial and dental anatomy in a way that students and nonexperts also may appreciate. Here, Clark argued against a teleology that might arise because the student of human evolution always knows how the story will end. Mechanisms proposed earlier to explain seeming evolutionary trends in the direction of living hominids, such as orthogenesis, were rejected.
However, whereas Clark denied the idea of inherent directional tendencies, which invoked a mysterious agency infused into the germ plasm of the evolving organism, impelling it along a predetermined course of evolution, he did see orthoselection as a possibility. It denoted the adaptation of a population to a narrow and restricted environment to a degree of specialization where further development could only mean a continuation of the trend. However, although the principle of the irreversibility of evolution was held as true for most cases, one had to allow for the possibility of retrogression.
While comparative anatomy and paleontology were presented as the main approaches through which to reconstruct primate phylogeny, blood reactions and protein structure analysis were accepted as important complementary tools (Nuttall, 1904; Goodman, 1963; the latter in later editions of Antecedents of Man, e.g., 3rd ed., 1971). In fact, the protein structure analysis functioned as collateral evidence that often confirmed long-standing insights from comparative anatomy. Once again, to determine taxonomic relationships, the comparative anatomist had to consider the organism as an entire functional unit:
This principle of taxonomic relevance is rather liable to be overlooked, particularly in the uncritical attempts which are sometimes made to quantify degrees of relationship by statistical comparisons of isolated measurements. Each natural group of animals is defined by a certain pattern of morphological characters which its members possess in common and which have been found by detailed studies to be sufficiently distinctive and consistent to distinguish its members from those of other related groups. The possession of this common morphological pattern can be taken to indicate a community of origin (in the evolutionary sense) of all the members of the group. (1971, p. 12)
A word of caution was also spoken with regard to the distinction between adaptive and nonadaptive traits, of which the latter had been considered as taxonomically more relevant, since in Clark’s integrative view it was often impossible to tell whether a trait might not be part of an intricate adaptational complex. In general, the book is illustrative of the post-synthesis era, with an emphasis on populations (rather than individual specimens) and the tendency to (again) interpret Australopithecus, Homo erectus, Homo sapiens as forming an evolutionary sequence (or at least as closely approaching such a sequence). These ideas can be generalized to primate evolution as a whole, where Clark recognized an overall evolutionary trend made up of tree-shrew, lemur, tarsier, monkey, ape, human, without suggesting that evolution had proceeded through these exact stages.
Obviously, the more linear interpretation of the hominid fossil record went along with taxonomic lumping. In fact, with regard to australopithecine taxonomy, Clark took the conservative view, rejecting subfamily status (Australopithecinae) and the subdivision into several genera (Australopithecus, Plesianthropus, Paranthropus). Rather, he adhered to the opinion that the australopithecine fossil remains represented species and varieties of one genus.
Final Years and Honors . Clark retired in 1962 but remained associated until his death in an honorary capacity with the Department of Anatomy at Oxford University, which he had transformed during the nearly thirty years as its head into one of the best schools in the country. Sadly, the year after his retirement his wife died, the former Freda Constance Giddey, with whom he had two daughters. Clark was remarried the following year, to Violet Browne. Once retired from the position of Dr. Lee’s professor of anatomy, he continued to make good use of his writing skills when telling the story of the australopithecine discoveries and controversies in chapters two through four of Man-Apes or Ape-Men? The Story of Discoveries in Africa (1967), in which he had played an important role. The remainder of the book summarized the interpretations of the teeth, skull, pelvis, and limb bones and provided an attempt at reconstructing the australopithecine ecology and evolutionary origins.
This was the time of the man-the-hunter paradigm. This hunting hypothesis shared wide popularity among anthropologists as an explanation for the evolution of adaptive behaviors. The human hallmarks of bipedalism, tool use, social cooperation and coordination, strategic reasoning (increased intelligence), and the differentiation of sex roles came to be explained on the basis of the male hunting way of life. The logic was that when human infants grew ever more dependent on their mothers due to postnatal neurological development, the male hunters had to become more efficient to care for the offspring as well as the encumbered females. Clark drew a picture of the australopithecines as tool-making hunters who must have had some form of social organization and communication system to be successful on the hunt in the open country. Life in the savannah was hostile and proto-“men” who were able to kill dangerous and sizable beasts might have turned against each other from time to time. However, Clark did not go as far as the American playwright, screenwriter, novelist, and popular writer of anthropology, Robert Ardrey, who claimed that men were inherently killer-apes, having inherited an instinct for murderous aggression that had been the driving force of all evolutionary progress (Ardrey, 1961, 1966).
Having tasted the sweetness of historical writing, Clark added to the account of the scientific career of the australopithecines that of his own. He wrote the story of his successes and contributions to science as “the doyen of British anatomy,” interspersed by fragmentary autobiographic memories, under the Whitmanian motto of a Chant of Pleasant Exploration (1968). Despite two world wars, it is a chant and not a hymn, and it is pleasant rather than sad: “One is left with the impression of a contemplative man who has explored the world both physically and intellectually, and who is not dissatisfied with what he found” (Day, 1969, p. 168). Clark died suddenly in Burton Bradstock, Dorset, on 28 June 1971, while visiting a friend from his student days.
Clark was a great authority in the world of anatomy and held honorary degrees from the universities of Durham, Edinburgh, Malaya, Manchester, Melbourne, Oslo, and Witwatersrand. He became a Fellow of the Royal College of Surgeons in 1919, was Arris and Gale Lecturer in 1932, and Hunterian Professor in 1934 and 1945. He was also editor of the Journal of Anatomy. He was president of the International Anatomical Congress in 1950, of the Anatomical Society of Great Britain in 1952, and the Anthropological Section of the British Association for the Advancement of Science in 1939 and 1961. He held honorary memberships in foreign academies and societies, among them the American Philosophical Society and the National Academy of Science in Washington. He was knighted in 1955, and the recipient of the Viking Fund Medal in 1956 and of the Royal Medal of the Royal Society in 1961.
BIBLIOGRAPHY
WORKS BY CLARK
“Notes on the Living Tarsier (Tarsius spectrum).” In Proceedings of the General Meetings for Scientific Business of the Zoological Society of London, vol.1. London : Longmans, Green, 1924a.
“On the Brain of the Tree-Shrew (Tupaia minor).” In Proceedings of the General Meetings for Scientific Business of the Zoological Society of London, vol. 2. London : Longmans, Green, 1924b.
“Studies on the Optic Thalamus of the Insectivora: The Anterior Nuclei.” Brain 52 (1929): 334–358.
“The Thalamus of Tarsius.” Journal of Anatomy 64 (1930):371–414.
“The Brain of Insectivora.” In Proceedings of the General Meetings for Scientific Business of the Zoological Society of London, vol.2. London : Longmans, Green, 1932.
“An Experimental Study of Thalamic Connections in the Rat.” Philosophical Transactions of the Royal Society, series B Biological Sciences, 222 (1933): 1–28.
Early Forerunners of Man: A Morphological Study of the Evolutionary Origin of the Primates. London: Ballière, Tindall, 1934.
“Evolutionary Parallelism and Human Phylogeny.” Man 36 (1936): 4–8.
With John Beattie, George Riddoch, and Norman M. Dott. The Hypothalamus: Morphological, Functional, Clinical, and Surgical Aspects. Edinburgh: Oliver and Boyd, 1938.
The Tissues of the Body: An Introduction to the Study of Anatomy. Oxford: Clarendon Press, 1939.
“Pan-African Congress on Prehistory: Human Palaeontological Section.” Man 47 (1947a): 101.
“The Importance of the Fossil Australopithecinae in the Study of Human Evolution.” Science Progress 35 (1947b): 377–395.
“Observations on the Anatomy of the Fossil Australopithecinae.” Journal of Anatomy 81 (1947c): 300–333.
History of the Primates: An Introduction to the Study of Fossil Man. London: Printed by order of the Trustees of the British Museum, 1949. (2nd ed., London: Trustees of the British Museum, 1950a; 10th ed., London: British Museum, 1970).
“Hominid Characters of the Australopithecine Dentition.” Journal of the Royal Anthropological Institute of Great Britain and Ireland 80 (1950): 37–54.
With Louis S. B. Leakey. “Diagnoses of East African Miocene Hominoidea.” Quarterly Journal of the Geological Society of London 105 (1950): 260–262.
With D. P. Thomas. The Miocene Lemuroids of East Africa. Fossil Mammals of Africa no. 5. London: British Museum (Natural History),1952.
Clark, Wilfrid Edward Le Gros, Joseph S. Weiner, and Kenneth Page Oakley. “The Solution of the Piltdown Problem.” Bulletin of the British Museum (Natural History), Geology Series 2 (1953): 141–146.
With Weiner, Joseph S.; Kenneth Page Oakley, et al. “Further Contributions to the Solution of the Piltdown Problem.” Bulletin of the British Museum (Natural History), Geology Series 2 (1955): 225–287.
The Fossil Evidence for Human Evolution: An Introduction to the Study of Paleoanthropology. Chicago: University of Chicago Press, 1955. (2nd ed., University of Chicago Press, 1964).
The Antecedents of Man: An Introduction to the Evolution of the Primates. Edinburgh: Edinburgh University Press, 1959 (3rd ed., Edinburgh: University Press, 1971).
Man-Apes or Ape-Men? The Story of Discoveries in Africa. London: Holt, Rinehart & Winston, 1967.
Chant of Pleasant Exploration. Edinburgh: E. & S. Livingstone, 1968.
OTHER SOURCES
Ardrey, Robert. African Genesis: A Personal Investigation into the Animal Origins and Nature of Man. New York: Atheneum, 1961.
———. The Territorial Imperative: A Personal Inquiry into the Animal Origins of Property and Nations. New York: Atheneum, 1966.
Ashton, E. H., and Solly Zuckerman. “Some Quantitative Dental Characteristics of Fossil Anthropoids.” Philosophical Transactions of the Royal Society, series B Biological Sciences, 234 (1950): 485–520.
———. “Statistical Methods in Anthropology.” Nature 168 (1951): 1117–1118.
Broom, Robert. Finding the Missing Link: An Account of Recent Discoveries Throwing New Light on the Origin of Man. London: Watts, 1950.
Day, M. H. Review of Chant of Pleasant Exploration. Man, n.s., 4, no. 1 (1969): 168.
Goodman, Morris. “Man’s Place in the Phylogeny of the Primates as Reflected in Serum Proteins.” In Classification and Human Evolution, edited by Sherwood Larned Washburn. London: Methuen, 1963.
Mayr, Ernst. “Taxonomic Categories in Fossil Hominids.” In Origin and Evolution of Man. Cold Spring Harbor Symposia on Quantitative Biology 15. Cold Spring Harbor, NY: The Biological Laboratory, 1950.
Nuttall, George H. F. Blood Immunity and Blood Relationship: A Demonstration of Certain Blood-Relationships amongst Animals by Means of the Precipitin Test for Blood. Cambridge, U.K.: Cambridge University Press, 1904.
Washburn, Sherwood Larned. “The New Physical Anthropology.” Transactions of the New York Academy of Sciences, series 2, 13 (1951): 298–304.
Weddell, G. “In Memoriam: Wilfrid Edward Le Gros Clark.” Journal of Anatomy 111 (1972): 181–184.
Zuckerman, Solly. “Wilfrid Edward Le Gros Clark, 1895–1971.” Biographical Memoirs of Fellows of the Royal Society 19 (1973): 217–233. See this memoir for a more comprehensive bibliography.
Marianne Sommer