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37-499: Camelidae and numerous prehistoric families (see text) Tylopoda (meaning "calloused foot") is a suborder of terrestrial herbivorous even-toed ungulates belonging to the order Artiodactyla . They are found in the wild in their native ranges of South America and Asia , while Australian feral camels are introduced . The group has a long fossil history in North America and Eurasia . Tylopoda appeared during

74-409: A correlation does not make a given case predicable, so ancestral characters should not be imputed to the members of a less species-rich basal clade without additional evidence. In general, clade A is more basal than clade B if B is a subgroup of the sister group of A or of A itself. In the context of large groups, the term "basal" is often used loosely to refer to positions closer to

111-698: A mix of archaic and apomorphic (derived) features that have only been sorted out via comparison with other angiosperms and their positions within the phylogenetic tree (the fossil record could potentially also be helpful in this respect, but is absent in this case). The cladogram below is based on Ramírez-Barahona et al. (2020), with species counts taken from the source indicated. Amborellales (1 species) Nymphaeales (about 90 species) Austrobaileyales (about 95 species) Magnoliids (about 9,000 species) Chloranthales (about 80 species) Monocots (about 70,000 species) Ceratophyllales (about 6 species) Eudicots (about 175,000 species) Within

148-640: A result of changing environmental conditions after the last ice age, or a combination of these factors. Three species groups survived - the dromedary of northern Africa and southwest Asia; the Bactrian camel of central Asia; and the South American group, which has now diverged into a range of forms that are closely related, but usually classified as four species - llamas , alpacas , guanacos , and vicuñas . Camelids were domesticated by early Andean peoples, and remain in use today. Fossil camelids show

185-473: A sister group to Homininae and are the basal genus in the great ape family Hominidae as a whole. Orangutans ( Pongo spp.) Humans ( Homo sapiens ) Chimpanzees ( Pan spp.) Gorillas ( Gorilla spp.) Subfamilies Homininae and Ponginae are both basal within Hominidae, but given that there are no nonbasal subfamilies in the cladogram it is unlikely the term would be applied to either. In general,

222-405: A statement to the effect that one group (e.g., orangutans) is basal, or branches off first, within another group (e.g., Hominidae) may not make sense unless the appropriate taxonomic level(s) (genus, in this case) is specified. If that level cannot be specified (i.e., if the clade in question is unranked) a more detailed description of the relevant sister groups may be needed. As can be seen, the term

259-461: A trait generally viewed as ancestral among the apes. Given that the deepest phylogenetic split in a group is likely to have occurred early in its history, identification of the most basal subclade(s) in a widely dispersed taxon or clade can provide valuable insight into its region of origin; however, the lack of additional species in a clade is not evidence that it carries the ancestral state for most traits. Most deceptively, people often believe that

296-404: A unique type of antibodies , which lack the light chain, in addition to the normal antibodies found in other mammals. These so-called heavy-chain antibodies are being used to develop single-domain antibodies with potential pharmaceutical applications. Camelids do not have hooves; rather, they have two-toed feet with toenails and soft foot pads ( Tylopoda is Greek for "padded foot"). Most of

333-443: A wider variety than their modern counterparts. One North American genus, Titanotylopus , stood 3.5 m at the shoulder, compared with about 2.0 m for the largest modern camelids. Other extinct camelids included small, gazelle-like animals, such as Stenomylus . Finally, a number of very tall, giraffe-like camelids were adapted to feeding on leaves from high trees, including such genera as Aepycamelus and Oxydactylus . Whether

370-553: Is a basal clade of extant angiosperms , consisting of the most species, genus, family and order within the group that are sister to all other angiosperms (out of a total of about 250,000 angiosperm species). The traits of Amborella trichopoda are regarded as providing significant insight into the evolution of flowering plants; for example, it has "the most primitive wood (consisting only of tracheids ), of any living angiosperm" as well as "simple, separate flower parts of indefinite numbers, and unsealed carpels". However, those traits are

407-419: Is almost the inverse of their area of origin. Camelids first appeared very early in the evolution of the even-toed ungulates, around 50 to 40 million years ago during the middle Eocene , in present-day North America. Among the earliest camelids was the rabbit-sized Protylopus , which still had four toes on each foot. By the late Eocene , around 35 million years ago, camelids such as Poebrotherium had lost

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444-415: Is likely a source of the mis-use of the term. Other famous examples of this phenomenon are the oviparous reproduction and nipple-less lactation of monotremes , a clade of mammals with just five species, and the archaic anatomy of the tuatara , a basal clade of lepidosaurian with a single species. The flowering plant family Amborellaceae , restricted to New Caledonia in the southwestern Pacific,

481-515: Is not reflective of ancestral states or proximity to the common ancestor of extant species. In this example, orangutans differ from the other genera in their Asian range. This fact plus their basal status provides a hint that the most recent common ancestor of extant great apes may have been Eurasian (see below), a suggestion that is consistent with other evidence. (Of course, lesser apes are entirely Asiatic.) However, orangutans also differ from African apes in their more highly arboreal lifestyle,

518-899: Is that the extensive fossil record of camel-like mammals has not yet been thoroughly examined from a cladistic standpoint. Tylopoda is a highly distinctive lineage among the artiodactyls , but its exact relationships are somewhat elusive because the six living species are all closely related and can be considered " living fossils ", the sole surviving lineage of a prehistorically wildly successful radiation . More recent studies suggest that tylopods are not as closely related to ruminants as traditionally believed, expressed in cladogram form as: Tylopoda (camels) [REDACTED]   Suina (pigs) [REDACTED]   Ruminantia (ruminants) [REDACTED]     Hippopotamidae (hippopotamuses) [REDACTED]   Cetacea (whales) [REDACTED] Tylopoda are extremely conservative in their lifestyle and (like ruminants) seem to have occupied

555-418: Is unnecessary and misleading. The term is more often applied when one branch (the one deemed "basal") is less diverse than another branch (this being the situation in which one would expect to find a basal taxon of lower minimum rank). The term may be equivocal in that it also refers to the direction of the root of the tree, which represents a hypothetical ancestor; this consequently may inaccurately imply that

592-491: The Eocene around 50 million years ago. Tylopoda has only one extant family, Camelidae , which includes camels , llamas , guanacos , alpacas and vicuñas . This group was much more diverse in the past, containing a number of extinct families in addition to the ancestors of living camelids (see below). Tylopods are not ruminants . Tylopoda was named by Illiger (1811) and considered monophyletic by Matthew (1908). It

629-586: The Great American Interchange ), giving rise to the modern llamas. A population of Paracamelus continued living in North America and evolved into the high arctic camel , which survived until the middle Pleistocene. The original camelids of North America remained common until the quite recent geological past, but then disappeared, possibly as a result of hunting or habitat alterations by the earliest human settlers , and possibly as

666-400: The even-toed ungulates and relatives means that the oldest members of this lineage are still morphologically very primitive and hard to distinguish from the ancestors of related lineages. The first major modern and comprehensive analysis of the problem (in 2009) supported this; while some taxa traditionally considered Tylopoda could be confirmed to belong to this suborder (and a few refuted),

703-590: The great apes , gorillas (eastern and western) are a sister group to chimpanzees , bonobos and humans . These five species form a clade, the subfamily Homininae (African apes), of which Gorilla has been termed the basal genus. However, if the analysis is not restricted to genera, the Homo plus Pan clade is also basal. Humans ( Homo sapiens ) Bonobos ( Pan paniscus ) Chimpanzees ( Pan troglodytes ) Eastern gorillas ( Gorilla beringei ) Western gorillas ( Gorilla gorilla ) Moreover, orangutans are

740-722: The molars by a gap. As in ruminants, the upper incisors are largely absent and are replaced by a dental pad consisting of connective tissue covered with epithelium . The musculature of the hind limbs differs from those of other ungulates in that the legs are attached to the body only at the top of the thigh, rather than attached by skin and muscle from the knee upwards. Because of this, camelids have to lie down by resting on their knees with their legs tucked underneath their bodies. They have three-chambered stomachs , rather than four-chambered ones; their upper lips are split in two, with each part separately mobile; and, uniquely among mammals, their red blood cells are elliptical. They also have

777-484: The order Artiodactyla , along with species including whales , pigs , deer , cattle , and antelopes . Camelids are large, strictly herbivorous animals with slender necks and long legs. They differ from ruminants in a number of ways. Their dentition show traces of vestigial central incisors in the incisive bone , and the third incisors have developed into canine-like tusks. Camelids also have true canine teeth and tusk-like premolars , which are separated from

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814-602: The (Cet)artiodactyla or as more closely related to other artiodactyl groups like ruminants : Some studies have considered Protoceratidae closely related to Tylopoda, but others have considered them more closely related to the ruminants . Camelidae Camelids are members of the biological family Camelidae , the only currently living family in the suborder Tylopoda . The seven extant members of this group are: dromedary camels , Bactrian camels , wild Bactrian camels , llamas , alpacas , vicuñas , and guanacos . Camelids are even-toed ungulates classified in

851-614: The Bactrian camel are even able to drink brackish water , and some herds live in nuclear test areas. Comparative table of the seven extant species in the family Camelidae: ( Camelus bactrianus ) ( Camelus dromedarius ) ( Camelus ferus ) ( Lama glama ) ( Lama guanicoe ) ( Lama pacos ) ( Lama vicugna ) L. glama L. guanicoe V. vicugna V. pacos C. bactrianus C. dromedarius C. kansanus C. hesternus C. minodokae Camelids are unusual in that their modern distribution

888-520: The delimitation of this group is still very much disputed despite (or because of) an extensive fossil record. The taxa currently assigned (with some reliability) to Tylopoda are: Basal and incertae sedis Superfamily Cameloidea Superfamily † Merycoidodontoidea (=Oreodontoidea) Several additional prehistoric (cet)artiodactyl taxa are sometimes assigned to the Tylopoda, but other authors consider them incertae sedis or basal lineages among

925-719: The extant taxa of a given rank within the clade; this is one reason the term basal is highly deceptive, as the lack of additional species in one clade is taken as evidence of morphological affinity with ancestral taxa. Additionally, this qualification does not ensure that the diversity of extinct taxa (which may be poorly known) is represented. In phylogenetics, the term basal cannot be objectively applied to clades of organisms, but tends to be applied selectively and more controversially to groups or lineages thought to possess ancestral characters, or to such presumed ancestral traits themselves. In describing characters, "ancestral" or " plesiomorphic " are preferred to "basal" or " primitive ",

962-403: The following case:   Basal clade #1  Non-basal clade #1  Non-basal clade #2    Non-basal clade #3 While it is easy to identify a basal clade in such a cladogram, the appropriateness of such an identification is dependent on the accuracy and completeness of the diagram. It is often assumed in this example that the terminal branches of the cladogram depict all

999-444: The foot. Many fossil camelids were unguligrade and probably hooved, in contrast to all living species. Camelids are behaviorally similar in many ways, including their walking gait, in which both legs on the same side are moved simultaneously. While running, camelids engage a unique "running pace gait" in which limbs on the same side move in the same pattern they walk, with both left legs moving and then both right, which ensures that

1036-473: The fore and hind limb will not collide while in fast motion. During this motion, all four limbs momentarily are off the ground at the same time. Consequently, camelids large enough for human beings to ride have a typical swaying motion. Dromedary camels, bactrian camels, llamas, and alpacas are all induced ovulators . The three Afro-Asian camel species have developed extensive adaptations to their lives in harsh, near-waterless environments. Wild populations of

1073-437: The latter of which may carry false connotations of inferiority or a lack of complexity. The terms ''deep-branching'' or ''early-branching'' are similar in meaning, and equally may misrepresent extant taxa that lie on branches connecting directly to the root node as having more ancestral character states. Despite the ubiquity of the usage of basal , systematists try to avoid its usage because its application to extant groups

1110-419: The root of every cladogram, those clades may differ widely in taxonomic rank , species diversity , or both. If C is a basal clade within D that has the lowest rank of all basal clades within D , C may be described as the basal taxon of that rank within D . The concept of a ' key innovation ' implies some degree of correlation between evolutionary innovation and diversification . However, such

1147-423: The root than the majority, and in such cases, expressions like "very basal" can appear. A 'core clade' refers to the grouping that encompasses all constituent clades except for the basal clade(s) of the lowest rank within a larger clade, exemplified by core eudicots . No extant taxon is closer to the root than any other. A basal group in the stricter sense forms a sister group to the rest of the larger clade, as in

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1184-453: The same ecological niche since their origin over 40 million years ago. Thus, it seems that the previous assumption of a close relationship between Tylopoda and ruminants is simply because all other close relatives (whales, pigs etc.) are so divergent in their adaptations as to have obscured most indications of relationship, or at least those visible to phenetic analyses. However, the rather basal position that Tylopoda appears to have among

1221-529: The sister group of a more species-rich clade displays ancestral features. An extant basal group may or may not resemble the last common ancestor of a larger clade to a greater degree than other groups, and is separated from that ancestor by the same amount of time as all other extant groups. However, there are cases where the unusually small size of a sister group does indeed correlate with an unusual number of ancestral traits, as in Amborella (see below). This

1258-612: The two lateral toes, and were about the size of a modern goat . The family diversified and prospered, with the two living tribes, the Camelini and Lamini , diverging in the late early Miocene , about 17 million years ago, but remained restricted to North America until about 6 million years ago, when Paracamelus crossed the Bering land bridge into Eurasia , giving rise to the modern camels, and about 3-2 million years ago, when Hemiauchenia emigrated into South America (as part of

1295-425: The weight of the animal rests on these tough, leathery sole pads. The South American camelids have adapted to the steep and rocky terrain by adjusting the pads on their toes to maintain grip. The surface area of Camels foot pads can increase with increasing velocity in order to reduce pressure on the feet and larger members of the camelid species will usually have larger pad area, which helps to distribute weight across

1332-792: The wild Bactrian camel ( Camelus ferus ) is a distinct species or a subspecies ( C. bactrianus ferus ) is still debated. The divergence date is 0.7 million years ago, long before the start of domestication. Family Camelidae Lama guanicoe Lama glama Lama pacos Lama vicugna Bactrian camel Dromedary In October 2017 the United Nations declared 2024 to be the International Year of Camelids in order to show how camelids are important for food security, economics and culture for many pastoral communities. Basal (evolution) While there must always be two or more equally "basal" clades sprouting from

1369-436: Was treated as an unranked clade by Matthew (1908) and as a suborder by Carroll (1988), Ursing et al. (2000) and Whistler and Webb (2005). It was assigned to Ruminantia by Matthew (1908); to Artiodactyla by Flower (1883) and Carroll (1988); to Neoselenodontia by Whistler and Webb (2005); and to Cetartiodactyla by Ursing et al. (2000) and by Agnarsson and May-Collado (2008). The main problem with circumscription of Tylopoda

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