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Darwinius

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In phylogenetics , an apomorphy (or derived trait ) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy ). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have evolved in their most recent common ancestor . In cladistics , synapomorphy implies homology .

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85-559: Darwinius is a genus within the infraorder Adapiformes , a group of basal strepsirrhine primates from the middle Eocene epoch . Its only known species, Darwinius masillae , lived approximately 47 million years ago ( Lutetian stage ) based on dating of the fossil site. The only known fossil, called Ida , was discovered in 1983 at the Messel pit , a disused quarry near the village of Messel , about 35 km (22 mi) southeast of Frankfurt , Germany. The fossil, divided into

170-499: A BioCode that would regulate all taxon names, but this attempt has so far failed because of firmly entrenched traditions in each community. Consider a particular species, the red fox , Vulpes vulpes : in the context of the Zoological Code , the specific epithet vulpes (small v ) identifies a particular species in the genus Vulpes (capital V ) which comprises all the "true" foxes. Their close relatives are all in

255-405: A grooming claw on the foot and a fused row of teeth, a toothcomb , in the bottom jaw. Digital reconstructions of Ida's teeth reveal that she has unerupted molars in her jaw , indicating by comparison with modern squirrel monkeys that she was 9–10 months old and would have weighed 485 grams (17.1 oz); it was also initially suggested that Darwininus reached adulthood at 36 months with

340-420: A "hybrid formula" that specifies the parentage, or may be given a name. For hybrids receiving a hybrid name , the same ranks apply, prefixed with notho (Greek: 'bastard'), with nothogenus as the highest permitted rank. If a different term for the rank was used in an old publication, but the intention is clear, botanical nomenclature specifies certain substitutions: Classifications of five species follow:

425-548: A German fossil dealer . Two German museums turned it down as too expensive. A year later at the Hamburg Fossil and Mineral Fair in December 2006, the dealer asked Norwegian vertebrate palaeontologist Jørn Hurum, who had done some previous deals, to discuss something privately. The dealer showed Hurum three high resolution colour photographs of the fossil and told him that the asking price was $ 1 million. Hurum knew that it

510-476: A body mass of 650–900 grams (23–32 oz), and that it likely had a maximum age of 20 years. Both the age of Ida's death and the possible adult body mass has been questioned by López-Torres and colleagues in 2015, who suggested that Ida would have died between 1.05 and 1.14 years (12 to 14 months) of age based on its dental erruptions resembling more of strepsirrhines , and that an adult Darwinius would have weighed between 622–642 grams (21.9–22.6 oz) based on

595-588: A ceremony at the American Museum of Natural History Hurum said that "This specimen is like finding the Lost Ark for archeologists" and "It is the scientific equivalent of the Holy Grail . This fossil will probably be the one that will be pictured in all textbooks for the next 100 years." Regarding the publicity, Matt Cartmill an anthropologist from Duke University said "The P.R. campaign on this fossil

680-584: A complete specimen and arrived at a private Wyoming museum in 1991. Analysis by Jens Franzen of the Natural History Museum of Basel , Switzerland revealed the mixed actual and faked nature of this slab. A comparison of the two slabs indicates that the forger had access to the whole fossil. The primary slab remained in Germany in the possession of a private collector who kept it secret for twenty years before deciding to sell it anonymously via

765-567: A fast evolutionary radiation that occurred long ago, such as the main taxa of placental mammals . In his landmark publications, such as the Systema Naturae , Carl Linnaeus used a ranking scale limited to kingdom, class, order, genus, species, and one rank below species. Today, the nomenclature is regulated by the nomenclature codes . There are seven main taxonomic ranks: kingdom, phylum or division, class, order, family, genus, and species. In addition, domain (proposed by Carl Woese )

850-477: A full cladistic analysis , and in a column in The Times he stated that a unique opportunity to communicate science had been lost, with press releases forestalling the necessary discovery and debate which should now proceed. Hurum considered that the risk of buying the fossil had paid off, and said that "You need an icon or two in a museum to drag people in, this is our Mona Lisa and it will be our Mona Lisa for

935-404: A level of secrecy which is hard to attain in modern circumstances. In interviews published on 27 May, Hurum stated that it was good that they had got the message out that primates were rooted deep in time, but that some of the slogans were too much and the publicity got completely out of control. He disclosed that he paid nearly $ 750,000 (£465,000) for the specimen, but felt it was worthwhile to make

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1020-638: A lower level may be denoted by adding the prefix " infra ", meaning lower , to the rank. For example, infra order (below suborder) or infra family (below subfamily). Botanical ranks categorize organisms based (often) on their relationships ( monophyly is not required by that clade, which does not even mention this word, nor that of " clade "). They start with Kingdom, then move to Division (or Phylum), Class, Order, Family, Genus, and Species. Taxa at each rank generally possess shared characteristics and evolutionary history. Understanding these ranks aids in taxonomy and studying biodiversity. There are definitions of

1105-399: A new rank at will, at any time, if they feel this is necessary. In doing so, there are some restrictions, which will vary with the nomenclature code that applies. The following is an artificial synthesis, solely for purposes of demonstration of absolute rank (but see notes), from most general to most specific: Ranks are assigned based on subjective dissimilarity, and do not fully reflect

1190-525: A now-extinct group of strepsirrhines along with a newly discovered 37-million-year-old Egyptian primate, Afradapis . Seiffert believes that characteristics that appeared to show a relationship to haplorrhines are due to convergent evolution and has said that "the PR hype surrounding the Darwinius description was very confusing.” The type specimen is missing only its left rear leg. It has been named Ida after

1275-459: A particular organism, it is usually not necessary to specify names at ranks other than these first two, within a set of taxa covered by a given rank-based code. However, this is not true globally because most rank-based codes are independent from each other, so there are many inter-code homonyms (the same name used for different organisms, often for an animal and for a taxon covered by the botanical code). For this reason, attempts were made at creating

1360-476: A potential ancestor to humans." Having previously experienced how the blogosphere had picked up on his work, and seen Chinese dinosaur finds the object of bad early descriptions from blogging, Jørn Hurum decided to orchestrate launch of the fossil in a combined scientific and public event. Atlantic Productions , which had cooperated with Hurum on a program on the Predator X , a giant pliosaur from Svalbard ,

1445-419: A report with interviews with Gingerich and with Tim White , who cautioned that "Lemur advocates will be delighted, but tarsier advocates will be underwhelmed". At about the same time a press release headed "World Renowned Scientists Reveal a Revolutionary Scientific Find That Will Change Everything" announced that the find was "lauded as the most significant scientific discovery of recent times." On May 19, 2009

1530-449: A significant transitional form (a "link") between the prosimian and simian ("anthropoid") primate lineages. Others have disagreed with this placement. Concerns have been raised about the claims made about the fossil's relative importance and the publicising of the fossil before adequate information was available for scrutiny by the academic community. Some of Norway's leading biologists, among them Nils Christian Stenseth , have called

1615-405: A slab and partial counterslab after the amateur excavation and sold separately, was not reassembled until 2007. The fossil is of a juvenile female, approximately 58 cm (23 in) overall length, with the head and body length excluding the tail being about 24 cm (9.4 in). It is estimated that Ida died at about 80–85% of her projected adult body and limb length. The genus Darwinius

1700-477: A synapomorphy is the marker for the most recent common ancestor of the monophyletic group consisting of a set of taxa in a cladogram. What counts as a synapomorphy for one clade may well be a primitive character or plesiomorphy at a less inclusive or nested clade. For example, the presence of mammary glands is a synapomorphy for mammals in relation to tetrapods but is a symplesiomorphy for mammals in relation to one another—rodents and primates, for example. So

1785-576: A taxon in a category above the species level). It should be a natural group (that is, non-artificial, non- polyphyletic ), as judged by a biologist, using all the information available to them. Equally ranked higher taxa in different phyla are not necessarily equivalent in terms of time of origin, phenotypic distinctiveness or number of lower-ranking included taxa (e.g., it is incorrect to assume that families of insects are in some way evolutionarily comparable to families of mollusks). Of all criteria that have been advocated to rank taxa, age of origin has been

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1870-460: A transitional fossil (a "missing link") between Strepsirrhini and Haplorrhini, and so could be ancestral to humans. They also suggest that tarsiers have been misplaced in the Haplorrhini and should be considered Strepsirrhini. To support this view they show that as many as six morphological traits found in "Darwinius" are derived characters present only in the Haplorrhini lineage, but absent in

1955-503: A wrist injury. Based on studies of ring-tailed lemurs , it is unlikely that this injury was fatal, as ring-tailed lemurs have been shown to survive and maintain their ability to climb with similar or more traumatic injuries. The events regarding the original unearthing of the fossil are not clear, though some facts are known. It was found at the Messel pit in 1983, a disused shale quarry noted for its astonishing fossil preservation, near

2040-464: Is I think more of a story than the fossil itself". Independent experts have raised concern about publicity exaggerating the importance of the find before information was available for scrutiny. Chris Beard, curator of the Carnegie Museum of Natural History , was "awestruck" by the publicity machine but concerned that if the hype was exaggerated, it could damage the popularisation of science if

2125-564: Is also called a binomial , that is, a two-term name. For example, the zoological name for the human species is Homo sapiens . This is usually italicized in print or underlined when italics are not available. In this case, Homo is the generic name and it is capitalized; sapiens indicates the species and it is not capitalized. While not always used, some species include a subspecific epithet. For instance, modern humans are Homo sapiens sapiens , or H. sapiens sapiens . In zoological nomenclature, higher taxon names are normally not italicized, but

2210-593: Is from an early group of primates just prior to diversification into the anthropoids (monkeys, apes and humans) and the prosimians (lemurs, lorises and tarsiers). Erik Seiffert and colleagues at Stony Brook University argue that Darwinius is on the branch towards the Strepsirrhini and is not a 'missing link' in the evolution of the Anthropoidea. A phylogenetic analysis of 360 morphological characters in 117 extinct and modern primates places Darwinius in

2295-467: Is not a requirement of the zoological and botanical codes. A classification in which all taxa have formal ranks cannot adequately reflect knowledge about phylogeny. Since taxon names are dependent on ranks in rank-based (Linnaean) nomenclature, taxa without ranks cannot be given names. Alternative approaches, such as phylogenetic nomenclature , as implemented under the PhyloCode and supported by

2380-435: Is now widely used as a fundamental rank, although it is not mentioned in any of the nomenclature codes, and is a synonym for dominion ( Latin : dominium ), introduced by Moore in 1974. A taxon is usually assigned a rank when it is given its formal name. The basic ranks are species and genus. When an organism is given a species name it is assigned to a genus, and the genus name is part of the species name. The species name

2465-406: Is part of nomenclature rather than taxonomy proper, according to some definitions of these terms) is the relative or absolute level of a group of organisms (a taxon ) in a hierarchy that reflects evolutionary relationships. Thus, the most inclusive clades (such as Eukarya and Opisthokonta ) have the highest ranks, whereas the least inclusive ones (such as Homo sapiens or Bufo bufo ) have

2550-439: Is usually associated with a certain body plan , which is also, however, an arbitrary criterion. Enigmatic taxa are taxonomic groups whose broader relationships are unknown or undefined. (See Incertae sedis .) There are several acronyms intended to help memorise the taxonomic hierarchy, such as "King Phillip came over for great spaghetti". (See taxonomy mnemonic .) Synapomorphy Examples of apomorphy are

2635-557: The Ancient Greek words σύν ( sún ), meaning "with, together"; ἀπό ( apó ), meaning "away from"; and μορφή ( morphḗ ), meaning "shape, form". Lampreys and sharks share some features, like a nervous system, that are not synapomorphic because they are also shared by invertebrates . In contrast, the presence of jaws and paired appendages in both sharks and dogs, but not in lampreys or close invertebrate relatives, identifies these traits as synapomorphies. This supports

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2720-789: The Botanical Code , the Prokaryotic Code , the Code for Viruses , the draft BioCode and the PhyloCode all recommend italicizing all taxon names (of all ranks). There are rules applying to the following taxonomic ranks in the International Code of Zoological Nomenclature : superfamily, family, subfamily, tribe, subtribe, genus, subgenus, species, subspecies. The International Code of Zoological Nomenclature divides names into "family-group names", "genus-group names" and "species-group names". The Code explicitly mentions

2805-483: The International Society for Phylogenetic Nomenclature , or using circumscriptional names , avoid this problem. The theoretical difficulty with superimposing taxonomic ranks over evolutionary trees is manifested as the boundary paradox which may be illustrated by Darwinian evolutionary models. There are no rules for how many species should make a genus, a family, or any other higher taxon (that is,

2890-727: The Prokaryotic Code , and the Code for Viruses ) require them. However, absolute ranks are not required in all nomenclatural systems for taxonomists; for instance, the PhyloCode , the code of phylogenetic nomenclature , does not require absolute ranks. Taxa are hierarchical groups of organisms, and their ranks describes their position in this hierarchy. High-ranking taxa (e.g. those considered to be domains or kingdoms, for instance) include more sub-taxa than low-ranking taxa (e.g. those considered genera, species or subspecies). The rank of these taxa reflects inheritance of traits or molecular features from common ancestors. The name of any species and genus are basic ; which means that to identify

2975-494: The cladistic analysis compared only 30 traits when standard practice is to analyze 200 to 400 traits and to include fossils such as anthropoids from Egypt and the primate genus Eosimias which were not included in the analysis. This contrasts with the motive openly stated by the authors, which was to list 30 anatomical and morphological characteristics "commonly used" to distinguish extant strepsirrhine and haplorrhine primates. Paleontologist Richard Kay of Duke University thought

3060-427: The fruit fly familiar in genetics laboratories ( Drosophila melanogaster ), humans ( Homo sapiens ), the peas used by Gregor Mendel in his discovery of genetics ( Pisum sativum ), the "fly agaric" mushroom Amanita muscaria , and the bacterium Escherichia coli . The eight major ranks are given in bold; a selection of minor ranks are given as well. Taxa above the genus level are often given names based on

3145-418: The type genus , with a standard termination. The terminations used in forming these names depend on the kingdom (and sometimes the phylum and class) as set out in the table below. Pronunciations given are the most Anglicized . More Latinate pronunciations are also common, particularly / ɑː / rather than / eɪ / for stressed a . There is an indeterminate number of ranks, as a taxonomist may invent

3230-633: The American Ornithologists' Union published in 1886 states "No one appears to have suspected, in 1842 [when the Strickland code was drafted], that the Linnaean system was not the permanent heritage of science, or that in a few years a theory of evolution was to sap its very foundations, by radically changing men's conceptions of those things to which names were to be furnished." Such ranks are used simply because they are required by

3315-482: The Eocene adapiforms." In an interview published on 27 May 2009, Jørn Hurum stated that he had an open mind about the possibility that the fossil might turn out to be a lemur and that a paper on systematics to be published within about a year would mainly focus on the partial counterslab containing the inner ear and the foot bones. Most experts hold that the higher primates (simians) evolved from Tarsiidae, branching off

3400-665: The Messel locality that belongs to the cercamoniine adapiforms, in addition to Europolemur koenigswaldi and Europolemur kelleri . Darwinius masillae is similar but not directly related to Godinotia neglecta from Geiseltal . The adapiforms are early primates which are known only from the fossil record, and it is unclear whether they form a monophyletic or a paraphyletic grouping. They are usually grouped under Strepsirrhini —including lemurs , aye-ayes and lorisoids —and as such would not be ancestral to Haplorrhini , which includes tarsiers and simians . Simians are usually called "anthropoid": while this term can be confusing,

3485-558: The Strepsirrhini before the appearance of the Adapiformes. A smaller group agrees with Franzen et al. that the higher primates descend from Adapiformes (Adapoidea). The view of paleontologist Tim White is that Darwinius is unlikely to end the argument. Philip D. Gingerich states that the seven superfamilies of primates are commonly associated in the higher taxonomic groupings of suborders Anthropoidea and Prosimii as an alternative to Haplorhini and Strepsirrhini, depending on

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3570-494: The Strepsirrhini lineage, which they interpret as synapomorphies . These include, among others, a cranium with a short rostrum, deep mandibular ramus , loss of all grooming claws. They note "that Darwinius masillae and adapoids contemporary with early tarsioids could represent a stem group from which later anthropoid primates evolved, but we are not advocating this here, nor do we consider either Darwinius or adapoids to be anthropoids." Paleontologists have expressed concern that

3655-549: The UK, directed by Tim Walker and produced by Lucie Ridout, to be screened six days later on the History Channel (US), BBC One (UK), and various stations in Germany and Norway. The New York Daily News noted that "The unveiling of the fossil came as part of an orchestrated publicity campaign unusual for scientific discoveries". One of the paper's co-authors, paleontologist Philip D. Gingerich , expressed dissatisfaction with

3740-531: The concept can be understood as well in terms of "a character newer than" ( autapomorphy ) and "a character older than" ( plesiomorphy ) the apomorphy: mammary glands are evolutionarily newer than vertebral column, so mammary glands are an autapomorphy if vertebral column is an apomorphy, but if mammary glands are the apomorphy being considered then vertebral column is a plesiomorphy. These phylogenetic terms are used to describe different patterns of ancestral and derived character or trait states as stated in

3825-462: The creature was not all that it was hyped up to be. Paleoanthropologist Elwyn Simons of Duke University stated that it is a wonderful specimen but most of the information had been previously known, and paleoanthropologist Peter Brown of the University of New England said that the paper had insufficient evidence that Darwinius was ancestral to the simians. Others have also criticized claims that

3910-622: The data could have been cherry-picked. Paleontologist Callum Ross of the University of Chicago considered the claim that Darwinius should be classified as haplorhine was "unsupportable in light of modern methods of classification." The opinion of Chris Beard, curator of vertebrate paleontology at the Carnegie Museum of Natural History , was that Darwinius was not a "missing link" between anthropoids and more primitive primates, but that further study of this remarkably complete specimen would be very informative and could reveal relationships amongst "the earliest and least human-like of all known primates,

3995-483: The daughter of Jørn Hurum , the Norwegian vertebrate paleontologist from the Natural History Museum, University of Oslo , who secured one section of the fossil from an anonymous owner and led the research. In addition to the bones, remains of Ida's soft tissue and fur outline are present along with remnants of her last meal of fruit and leaves. The animal is about 58 cm (23 in) from nose to tail, or roughly

4080-432: The family Canidae , which includes dogs, wolves, jackals, and all foxes; the next higher major taxon, Carnivora (considered an order), includes caniforms (bears, seals, weasels, skunks, raccoons and all those mentioned above), and feliforms (cats, civets, hyenas, mongooses). Carnivorans are one group of the hairy, warm-blooded, nursing members of the class Mammalia , which are classified among animals with notochords in

4165-599: The following ranks for these categories: The rules in the Code apply to the ranks of superfamily to subspecies, and only to some extent to those above the rank of superfamily. Among "genus-group names" and "species-group names" no further ranks are officially allowed, which creates problems when naming taxa in these groups in speciose clades, such as Rana . Zoologists sometimes use additional terms such as species group , species subgroup , species complex and superspecies for convenience as extra, but unofficial, ranks between

4250-464: The following taxonomic categories in the International Code of Nomenclature for Cultivated Plants : cultivar group , cultivar , grex . The rules in the ICN apply primarily to the ranks of family and below, and only to some extent to those above the rank of family. (See also descriptive botanical name .) Taxa at the rank of genus and above have a botanical name in one part (unitary name); those at

4335-409: The fossil an "exaggerated hoax " and stated that its presentation and popular dissemination "fundamentally violate scientific principles and ethics ." Franzen et al. (2009) place the genus Darwinius in the subfamily Cercamoniinae of the family Notharctidae within the extinct infraorder Adapiformes of early primates . Darwinius masillae is the third primate species to be discovered at

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4420-547: The fossil available for scientific investigation instead of it being bought by a private collector and hidden away. Others including Chris Beard were concerned that the price and publicity could lead to profiteering by amateur collectors, and make acquisition of specimens for research purposes more difficult. The following television documentary about Ida has been broadcast. The US version is available on DVD. Taxonomic rank In biology , taxonomic rank (which some authors prefer to call nomenclatural rank because ranking

4505-434: The fossil represents the "missing link in human evolution", arguing that there is no such thing unless evolution is visualized as a chain as there are an enormous number of missing branches , and that while the fossil is a primate, there is no evidence to suggest that its species is a direct ancestor of humans. ScienceBlogger Brian Switek questioned the sensationalist coverage of claims of ancestral relationships made before

4590-480: The gradational nature of variation within nature. These problems were already identified by Willi Hennig , who advocated dropping them in 1969, and this position gathered support from Graham C. D. Griffiths only a few years later. In fact, these ranks were proposed in a fixist context and the advent of evolution sapped the foundations of this system, as was recognised long ago; the introduction of The Code of Nomenclature and Check-list of North American Birds Adopted by

4675-428: The growth model of lemurids . The shape of Ida's teeth provides clues as to her diet; jagged molars would have allowed her to slice food, suggesting that she was a leaf and seed eater. This is confirmed by the remarkable preservation of her gut content. Furthermore, the lack of a baculum (penis bone) found in all lower primates means that the fossil was from a female. X-rays performed on Ida revealed that her right wrist

4760-434: The hierarchy of taxa (hence, their ranks) does not necessarily reflect the hierarchy of clades . While older approaches to taxonomic classification were phenomenological, forming groups on the basis of similarities in appearance, organic structure and behavior, two important new methods developed in the second half of the 20th century changed drastically taxonomic practice. One is the advent of cladistics , which stemmed from

4845-510: The hypothesis that dogs and sharks are more closely related to each other than to lampreys. The concept of synapomorphy depends on a given clade in the tree of life. Cladograms are diagrams that depict evolutionary relationships within groups of taxa. These illustrations are accurate predictive device in modern genetics. They are usually depicted in either tree or ladder form. Synapomorphies then create evidence for historical relationships and their associated hierarchical structure. Evolutionarily,

4930-435: The length of manuscript or number of illustrations, and " PLoS ONE is the quickest way to publish a large work in the world!" At the time its discovery was announced in the scientific and the popular press, the fossil was characterized as the "most complete fossil primate ever discovered"; Sir David Attenborough has described it as "extraordinary". Google commemorated the unveiling with a themed logo on May 20, 2009. During

5015-422: The lowest ranks. Ranks can be either relative and be denoted by an indented taxonomy in which the level of indentation reflects the rank, or absolute, in which various terms, such as species , genus , family , order , class , phylum , kingdom , and domain designate rank. This page emphasizes absolute ranks and the rank-based codes (the Zoological Code , the Botanical Code , the Code for Cultivated Plants ,

5100-514: The media campaign, telling The Wall Street Journal that they had chosen to publish in PLoS ONE as "There was a TV company involved and time pressure" and they had been pushed to finish the study. "It's not how I like to do science", Gingerich concluded. In an interview, Jørn Hurum said that PLoS ONE had been chosen as it was open access and the research had been funded by Norwegian taxpayers who would benefit from free access, it did not restrict

5185-405: The most basic (or important) is the species, but this opinion is not universally shared. Thus, species are not necessarily more sharply defined than taxa at any other rank, and in fact, given the phenotypic gaps created by extinction, in practice, the reverse is often the case. Ideally, a taxon is intended to represent a clade , that is, the phylogeny of the organisms under discussion, but this

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5270-409: The most frequently advocated. Willi Hennig proposed it in 1966, but he concluded in 1969 that this system was unworkable and suggested dropping absolute ranks. However, the idea of ranking taxa using the age of origin (either as the sole criterion, or as one of the main ones) persists under the name of time banding, and is still advocated by several authors. For animals, at least the phylum rank

5355-404: The next 100 years." He has been described as "a modern-era, media-savvy scientist with the right amounts of showmanship, populist sensibility, and disregard for the normal avenues of scientific prestige required to pull this off". The debut in "an astonishingly slick, multi-component media package" required exceptional coordination between networks, museums, producers and scientists while maintaining

5440-449: The paper uses it, as does associated publicity material. Simians (anthropoids) include monkeys and apes , which in turn includes humans. Franzen et al. in their 2009 paper place Darwinius in the " Adapoidea group of early primates representative of early haplorhine diversification". This means that, according to these authors, the adapiforms would not be entirely within the Strepsirrhini lineage as hitherto assumed, but would qualify as

5525-479: The phylum Chordata , and with them among all animals in the kingdom Animalia . Finally, at the highest rank all of these are grouped together with all other organisms possessing cell nuclei in the domain Eukarya . The International Code of Zoological Nomenclature defines rank as: "The level, for nomenclatural purposes, of a taxon in a taxonomic hierarchy (e.g. all families are for nomenclatural purposes at

5610-621: The position of Adapoidea and Tarsioidea. He puts forward a phylogeny in which the higher primates evolved from Darwinius , which he groups with other Adapoidea. He shows the Adapoidea together with the Tarsioidea as representing early diversification of the suborder Haplorhini and shows the Strepsirrhini as having branched off directly from the earliest primates. The Revealing the Link website uses this taxonomic grouping and states that Darwinius

5695-492: The presence of erect gait , fur , the evolution of three middle ear bones , and mammary glands in mammals but not in other vertebrate animals such as amphibians or reptiles , which have retained their ancestral traits of a sprawling gait and lack of fur. Thus, these derived traits are also synapomorphies of mammals in general as they are not shared by other vertebrate animals. The word synapomorphy —coined by German entomologist Willi Hennig —is derived from

5780-556: The project secret. A deal went through in the summer of 2008 with The History Channel which has been reported as paying more for this than any other documentary. The team decided to publish their findings online in PLoS ONE , an open access journal of the Public Library of Science . The paper for publication was received by PLoS ONE on March 19, 2009 and accepted on May 12, 2009. On 15 May The Wall Street Journal carried

5865-455: The rank of species and above (but below genus) have a botanical name in two parts ( binary name ); all taxa below the rank of species have a botanical name in three parts (an infraspecific name ). To indicate the rank of the infraspecific name, a "connecting term" is needed. Thus Poa secunda subsp. juncifolia , where "subsp". is an abbreviation for "subspecies", is the name of a subspecies of Poa secunda . Hybrids can be specified either by

5950-653: The rank-based codes; because of this, some systematists prefer to call them nomenclatural ranks . In most cases, higher taxonomic groupings arise further back in time, simply because the most inclusive taxa necessarily appeared first. Furthermore, the diversity in some major taxa (such as vertebrates and angiosperms ) is better known that that of others (such as fungi , arthropods and nematodes ) not because they are more diverse than other taxa, but because they are more easily sampled and studied than other taxa, or because they attract more interest and funding for research. Of these many ranks, many systematists consider that

6035-468: The same rank, which lies between superfamily and subfamily)." Note that the discussions on this page generally assume that taxa are clades ( monophyletic groups of organisms), but this is required neither by the International Code of Zoological Nomenclature nor by the Botanical Code , and some experts on biological nomenclature do not think that this should be required, and in that case,

6120-413: The size of a small, long-tailed cat. The lemur -like skeleton of the fossil features primate characteristics of grasping hands with opposable thumbs and nails instead of claws. These would have provided a "precision grip" which, for Ida, was useful for climbing and gathering fruit. Ida also has flexible arms and relatively short limbs. The fossil is missing two anatomical features found in modern lemurs:

6205-485: The subgenus and species levels in taxa with many species, e.g. the genus Drosophila . (Note the potentially confusing use of "species group" as both a category of ranks as well as an unofficial rank itself. For this reason, Alain Dubois has been using the alternative expressions "nominal-series", "family-series", "genus-series" and "species-series" (among others) at least since 2000. ) At higher ranks (family and above)

6290-509: The team revealed their findings to the world at a press conference simultaneously with online publication of the paper in PLoS ONE (for naming purposes, the paper was officially published in print on May 21, 2009). The paper included a statement that the authors were not advocating the possibility that the species could be ancestral to later anthropoid primates; Professor John Fleagle, of Stony Brook University in New York state, asserted that he

6375-661: The textbooks for the next 100 years" and compared its importance to the Mona Lisa . He also said that Darwinius was "the closest thing we can get to a direct ancestor" and that finding it was "a dream come true". Team member Jens Franzen said the state of preservation was "like the Eighth Wonder of the World", with information "palaeontologists can normally only dream of", but while he said it bore "a close resemblance to ourselves" in some aspects, other features indicated that it

6460-473: The village of Messel about 35 km (22 mi) southeast of Frankfurt am Main in Germany . The fossil came as a slab and partial counter slab and was expertly prepared by encasing each slab in resin using the transfer technique necessary to conserve Messel fossils. At some point the slab and counter slab went separate ways. The counter slab was incorporated in a composite of fabricated parts to represent

6545-727: The works of the German entomologist Willi Hennig . Cladistics is a method of classification of life forms according to the proportion of characteristics that they have in common (called synapomorphies ). It is assumed that the higher the proportion of characteristics that two organisms share, the more recently they both came from a common ancestor. The second one is molecular systematics, based on genetic analysis , which can provide much additional data that prove especially useful when few phenotypic characters can resolve relationships, as, for instance, in many viruses , bacteria and archaea , or to resolve relationships between taxa that arose in

6630-416: Was a primate and according to Tudge's book "was fast concluding that the specimen he was looking at could be one of the holy grails of science — the 'missing link' from the crucial time period." He asked for time until after Christmas to organise funding to pay for the specimen and ensure that it had been legally collected, had an export permit and would be legitimately available for study. His first choice

6715-543: Was brought in on the project in order to "take story straight to the masses in a way that would appeal to the average person, especially kids". The press conference and paper on the fossil was accompanied by the launch of a website the publication of a book which had already been distributed to bookstores, The Link: Uncovering Our Earliest Ancestor by Colin Tudge , and the announcement of a documentary ( Uncovering Our Earliest Ancestor: The Link ), made by Atlantic Productions in

6800-416: Was healing from a fracture which may have contributed to her death. The scientists speculate whether she was overcome by carbon dioxide fumes while drinking from the Messel lake. Hampered by her broken wrist, she slipped into unconsciousness, was washed into the lake and sank to the bottom, where unique fossilisation conditions preserved her for 47 million years. The type specimen of D. masillae exhibits

6885-404: Was named in commemoration of the bicentenary of the birth of Charles Darwin , and the species name masillae honors Messel where the specimen was found. The creature appeared superficially similar to a modern lemur . The authors of the paper describing Darwinius classified it as a member of the primate family Notharctidae , subfamily Cercamoniinae , suggesting that it has the status of

6970-457: Was not a direct ancestor. Independent experts were quick to question the claims. Henry Gee , a senior editor at Nature , said the term "missing link" was misleading and that the scientific community would need to evaluate its significance, which was unlikely to match that of Homo floresiensis or feathered dinosaurs . Chris Beard, curator of the Carnegie Museum of Natural History , said he "would be absolutely dumbfounded if it turns out to be

7055-429: Was one of the anonymous scientific reviewers of the paper and that he had explicitly requested before publication that the authors tone down their original claims that the fossil was on the human evolutionary line. At the press conference the fossil was described as the "missing link" in human evolution. Hurum said that “this fossil rewrites our understanding of the evolution of primates...it will probably be pictured in all

7140-544: Was studied in secret for two years by a team of scientists led by Hurum, who was joined by primate evolution expert Professor Philip Gingerich of the University of Michigan and palaeontologists Jens Franzen, who had studied the counter slab, and Jörg Habersetzer of the Senckenberg Museum 's Research Institute. While studies were in progress, negotiations were put in place for a book and with various broadcasters for documentary programs, all of whom agreed to keep

7225-597: Was the Natural History Museum of Oslo, but it was beyond their means and he began to think of other museums with sponsors available. He persuaded the Oslo museum to make half the funding available with the remainder to be paid only after X-ray scans proved conclusively that it was not a fake, a process which took several months. He put together a team including leading German experts on the Messel fossils, ensuring international ownership. After its acquisition it

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