Gomphotheres are any members of the diverse, extinct taxonomic family Gomphotheriidae. Gomphotheres were

elephant Elephants are the largest existing land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are the only surviving members of the family Elephantidae ...

-like

proboscidean The Proboscidea (; , ) are a taxonomic order of afrotherian mammals containing one living family (Elephantidae) and several extinct families. First described by J. Illiger in 1811, it encompasses the elephants and their close relatives. From ...

s, but do not belong to the family

Elephantidae Elephantidae is a family of large, herbivorous proboscidean mammals collectively called elephants and mammoths. These are terrestrial large mammals with a snout modified into a trunk and teeth modified into tusks. Most genera and species in the ...

. They were widespread across Afro-Eurasia and North America during the

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

and

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sout ...

during the

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...

following the Great American Interchange. Gomphotheriidae in its broadest sense is probably paraphyletic with respect to

, which contains modern elephants. While most famous forms such as ''

Gomphotherium ''Gomphotherium'' (; "welded beast") is an extinct genus of proboscids from the Neogene and early Pleistocene of Eurasia, Africa, North America and Asia. As of 2021, two species, ''G. annectens'' and possibly ''G. subtapiroideum'', are also k ...

'' had long lower jaws with tusks, which is the ancestral condition for the group, after these forms became extinct, the surviving gomphotheres had short jaws with either vestigial or no lower tusks (brevirostrine), looking very similar to modern elephants, an example of

parallel evolution Parallel evolution is the similar development of a trait in distinct species that are not closely related, but share a similar original trait in response to similar evolutionary pressure.Zhang, J. and Kumar, S. 1997Detection of convergent and paral ...

. By the end of the Early Pleistocene, gomphotheres became extinct in Afro-Eurasia, with the last two genera, ''

Cuvieronius ''Cuvieronius'' is an extinct New World genus of gomphothere, named after the French naturalist Georges Cuvier. Alive, specimens typically stood about tall at the shoulder, weighed about and would have superficially resembled a modern elephant ...

'' persisting in southern North America and ''

Notiomastodon ''Notiomastodon'' is an extinct proboscidean genus of gomphotheres (a distant relative to modern elephants) endemic to South America from the Pleistocene to the beginning of the Holocene. ''Notiomastodon'' specimens reached a size similar to that ...

'' having a wide range over most of South America until the end of the Pleistocene, when they became extinct following the arrival of humans. The name "gomphothere" comes from

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...

(), "peg, pin; wedge; joint" plus (), "beast".

Evolutionary history

The relationships of gomphotheres to other proboscideans remain unclear, and to some extent the grouping is a

wastebasket taxon Wastebasket taxon (also called a wastebin taxon, dustbin taxon or catch-all taxon) is a term used by some taxonomists to refer to a taxon that has the sole purpose of classifying organisms that do not fit anywhere else. They are typically defined ...

to refer to proboscideans that cannot be assigned to other groups. Gomphotheres originated in Africa during the Miocene, and arrived in Eurasia after the connection of Africa and Eurasia during the Early Miocene around 19 million years ago, in what is termed the " Proboscidean Datum Event". ''Gomphotherium'' arrived in North America around 16 million years ago. ''

'' and ''

'' dispersed into South America after 2 million years ago as part of the

Great American Biotic Interchange The Great American Biotic Interchange (commonly abbreviated as GABI), also known as the Great American Interchange and the Great American Faunal Interchange, was an important late Cenozoic paleozoogeographic biotic interchange event in which lan ...

due to the formation of the Isthmus of Panama. The last known gomphothere native to Eurasia was '' Sinomastodon'', which became extinct at the end of the Early Pleistocene.

Description

Gomphotheres differed from elephants in their

tooth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, t ...

structure, particularly the chewing surfaces on the molar teeth. The earlier species had four

tusk Tusks are elongated, continuously growing front teeth that protrude well beyond the mouth of certain mammal species. They are most commonly canine teeth, as with pigs and walruses, or, in the case of elephants, elongated incisors. Tusks share ...

s, and their retracted facial and nasal bones prompted

paleontologists Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of foss ...

to believe that gomphotheres had elephant-like trunks.

Taxonomy

Both the genus ''

'' and family Gomphotheriidae were erected by the German zoologist Karl Hermann Konrad Burmeister (1807-1892) in 1837. The term gomphothere as historically used (''sensu lato'') is paraphyletic, containing all proboscideans more derived than mammutids, but less derived than elephantids. The term gomphothere ''sensu stricto'' refers specifically to trilophodont gomphotheres. The genera ''

Anancus ''Anancus'' is an extinct genus of elephantoid proboscideans ("gomphothere" ''sensu lato'') native to Afro-Eurasia, that lived from the Tortonian stage of the late Miocene until the genus' extinction during the early Pleistocene, roughly from 8.5 ...

'', ''

Morrillia ''Stegomastodon'' ('roof breast tooth') is an extinct genus of gomphotheres, a family of proboscideans. It ranged throughout North America from the early Blancan ~4 Ma, to the early Irvingtonian (~1.2 Ma). The South American species have been s ...

'', '' Paratetralophodon'', and ''

Tetralophodon ''Tetralophodon'' ("four-ridged tooth") is an extinct proboscidean genus belonging to the superfamily Elephantoidea. Taxonomy The genus ''Tetralophodon'' (meaning "four-ridged tooth") was named in the mid-19th century with the discovery of the ...

'', but also the families Choerolophodontidae and

Amebelodontidae Amebelodontidae is an extinct family of large herbivorous mammals that were closely related to elephant Elephants are the largest existing land animals. Three living species are currently recognised: the African bush elephant, the African ...

, were formerly classified as gomphotheres ''sensu lato''. Tetralophodont gompotheres are more closely related to the Elephantidae and amebelodonts and choerolophodonts more primitive than trilophodont gomphotheres. In 2019, a study using collagen sequencing found ''

'' to form a clade with the

American mastodon American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, p ...

, rather than closer to the Elephantidae, as had previously been supposed. The idea that the Mammutidae and Gomphotheriidae are closely related was supported by a morphological study in 2020, which noted the similarity of the molars of the newly resurrected mammutid genus '' Miomastodon'' and those of ''Gomphotherium subtapiroideum/tassyi''. However this was contradicted by a 2021 study using Mitochondrial DNA from ''Notiomastodon'', which again found a closer relationship with elephants. Phylogeny of trilophodont gomphotheres according to Mothé et al., 2016:

Diet

Isotopic analyses of South American gomphotheres suggest a wide diet for ''

platensis'', except for the fossils unearthed at the localities in Santiago del Estero and La Carolina in Ecuador. Isotope analyses suggested an exclusive C4 diet, whereas every other South American locality indicates an exclusive C3 or mixed C3 and C4 diets. The results also support the latitudinal gradient of C3 and C4 grasses. The stereomicrowear analyses for ''N. platensis'' exhibited average scratch and pit values, which place it within the extant mixed-feeder morphospace and the higher frequency of fine scratches indicated the ingestion of C3 grasses. Alternatively, the presence of coarse and hypercoarse scratches along with gouges and large pits suggests the ingestion of foliage and lignified portions. The plant

microfossil A microfossil is a fossil that is generally between 0.001 mm and 1 mm in size, the visual study of which requires the use of light or electron microscopy. A fossil which can be studied with the naked eye or low-powered magnification, ...

analysis recovered fragments of conifer tracheid and vessel elements with a ray of parenchyma cells, which corroborates the consumption of woody plants,

pollen grains Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametop ...

spores In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, ...

, and fibers. The Aguas de Araxa gomphotheres were generalist feeders and consumed wood elements, leaves, and C3 grasses. ''

'' specimens from Chile were exclusively C3 plant eaters, whereas specimens from Bolivia and Ecuador are classified as having a mixed C3 and C4 diet. ''Notiomastodon'' showed a wider range of dietary adaptations. Specimens from Quequen Salado in Buenos Aires Province were entirely C3 feeders, whereas the diet of specimens from La Carolina Peninsula in Ecuador was exclusively C4.

Possible causes for extinction

The results confirm that ancient diets cannot always be interpreted solely from dental morphology or extrapolated from present relatives. The data from Middle and Late Pleistocene periods indicate that over time, a shift occurred in dietary patterns away from predominantly mixed feeders to more specialized feeders. This dietary evolution may have been one of the factors that contributed to the disappearance of South American gomphotheres at the end of the Pleistocene. Climatic change and human predation have also been discussed as possible causes of extinction.

Associations with early human sites

Gomphothere remains are common at South American Paleo-Indian sites. Examples include the early human settlement at

Monte Verde Monte Verde is an archaeological site in the Llanquihue Province in southern Chile, located near Puerto Montt, Southern Chile, which has been dated to as early as 18,500 cal BP (16,500 BC). Previously, the widely accepted date for early occu ...

, Chile, dating to around 14,000 years ago, and the

Altiplano Cundiboyacense The Altiplano Cundiboyacense () is a high plateau located in the Eastern Cordillera of the Colombian Andes covering parts of the departments of Cundinamarca and Boyacá. The altiplano corresponds to the ancient territory of the Muisca. The Alt ...

(

Tibitó Tibitó is the second-oldest dated archaeological site on the Altiplano Cundiboyacense, Colombia. In 2011, remains dating between 10,600 and 11,600 years ago were also found in the El Fin del Mundo (End of the World) site in Sonora,

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

's Clovis location – the first time such an association was found in a northern part of the continent where gomphotheres had been thought to have gone extinct 30,000 years ago. As announced in July 2014, the "position and proximity of Clovis weapon fragments relative to the gomphothere bones at the site suggest that humans did in fact kill the two animals there. Of the seven Clovis points found at the site, four were in place among the bones, including one with bone and teeth fragments above and below. The other three points had clearly eroded away from the bone bed and were found scattered nearby."

Gallery

References

External links

* (article about a fossil exhibit at the Sierra College Natural History Museum) * * (photos from the excavation of a Gomphothere skeleton on the

Sierra College Sierra College is a public community college in Rocklin, California. It is part of the Sierra Joint Community College District, a district that covers over , serves Placer, Nevada and parts of El Dorado and Sacramento counties. History The co ...

website) * {{Taxonbar, from=Q387585 Miocene proboscideans Pliocene proboscideans Serravallian first appearances Holocene extinctions Pleistocene proboscideans Taxa named by Ángel Cabrera de:Gomphotherium