''Ceratotherium mauritanicum'' is an extinct

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of African

rhinoceros A rhinoceros ( ; ; ; : rhinoceros or rhinoceroses), commonly abbreviated to rhino, is a member of any of the five extant taxon, extant species (or numerous extinct species) of odd-toed ungulates (perissodactyls) in the family (biology), famil ...

whose fossils are primarily known from the

Late Pliocene Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * Late (The 77s album), ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudo ...

to early

Late Pleistocene The Late Pleistocene is an unofficial Age (geology), age in the international geologic timescale in chronostratigraphy, also known as the Upper Pleistocene from a Stratigraphy, stratigraphic perspective. It is intended to be the fourth division ...

North Africa North Africa (sometimes Northern Africa) is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region. However, it is sometimes defined as stretching from the Atlantic shores of t ...

, specifically in

Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...

Tunisia Tunisia, officially the Republic of Tunisia, is a country in the Maghreb region of North Africa. It is bordered by Algeria to the west and southwest, Libya to the southeast, and the Mediterranean Sea to the north and east. Tunisia also shares m ...

, and

Algeria Algeria, officially the People's Democratic Republic of Algeria, is a country in the Maghreb region of North Africa. It is bordered to Algeria–Tunisia border, the northeast by Tunisia; to Algeria–Libya border, the east by Libya; to Alger ...

. The classification of certain Pliocene remains from East Africa as ''C. mauritanicum'' is debated, which in turn affects discussions about whether it was directly ancestral to the modern

white rhinoceros The white rhinoceros, also known as the white rhino or square-lipped rhinoceros (''Ceratotherium simum''), is the largest extant species of rhinoceros and the most Sociality, social of all rhino species, characterized by its wide mouth adapted f ...

(''Ceratotherium simum''). Current evidence suggests that ''C. mauritanicum'' was replaced in North Africa by ''C. simum'' during the early Late Pleistocene, between approximately 120,000 and 57,000 years ago.

Taxonomy and characteristics

The

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

position of ''Ceratotherium mauritanicum'' is subject to ongoing scientific discussion. One model, proposed by Geraads (2005), places it in a direct ancestral line between the earlier '' Ceratotherium neumayri'' (itself of debated generic placement) and the extant '' C. simum''. An alternative hypothesis, suggested by Hernesniemi et al. (2011), posits ''C. mauritanicum'' as a descendant of ''Ceratotherium efficax'' and an extinct

sister taxon In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

to ''C. simum''. This view suggests that ''C. mauritanicum'' retained more primitive characteristics in North Africa while the ''Ceratotherium'' lineage underwent more progressive evolution in eastern and

southern Africa Southern Africa is the southernmost region of Africa. No definition is agreed upon, but some groupings include the United Nations geoscheme for Africa, United Nations geoscheme, the intergovernmental Southern African Development Community, and ...

. The relationship between ''C. mauritanicum'' and ''Ceratotherium efficax'' (described from Pliocene East African fossils) is particularly complex. Some Pliocene fossils from East Africa have been attributed to ''C. mauritanicum'' by some authors, while the 2011 study by Hernesniemi et al. proposed these represented the distinct, more primitive ''C. efficax''. However, a subsequent study by Geraads (2020) concluded that ''C. efficax'' is synonymous with ''C. mauritanicum'', effectively lumping these Pliocene East African forms into an earlier phase of ''C. mauritanicum''. This synonymy is reflected in the speciesbox. ''Ceratotherium mauritanicum'' was widely distributed across northwestern Africa during the

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS), as well as the current and most recent of the twelve periods of the ...

and is frequently found in association with

archaeological Archaeology or archeology is the study of human activity through the recovery and analysis of material culture. The archaeological record consists of Artifact (archaeology), artifacts, architecture, biofact (archaeology), biofacts or ecofacts, ...

sites.

Petroglyph A petroglyph is an image created by removing part of a rock surface by incising, picking, carving, or abrading, as a form of rock art. Outside North America, scholars often use terms such as "carving", "engraving", or other descriptions ...

s (rock carvings) in North Africa sometimes depict rhinoceroses, though their schematic nature often makes species identification difficult. It is plausible that carvings showing characteristics typical of the white rhinoceros may actually represent ''C. mauritanicum'', which likely had a very similar external appearance to ''C. simum''. Morphologically, most characters distinguishing ''C. mauritanicum'' from ''C. simum'' involve minor proportional differences. The most readily discernible distinction is considered to be the more robust limb bones, particularly the metapodials, of ''C. simum''. Recent chronological studies indicate that ''C. mauritanicum'' disappeared from North Africa and was replaced by the modern white rhinoceros (''C. simum'') during a humid " Green Sahara" period in the early Late Pleistocene, specifically between 120,000 and 57,000 years ago.

Paleoecology

The paleoecology of ''Ceratotherium mauritanicum'' is thought to mirror that of the extant ''C. simum''. It likely inhabited open

savannah A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach th ...

landscapes that featured sufficient water sources and abundant grasses, a type of biome that has largely vanished from the

Maghreb The Maghreb (; ), also known as the Arab Maghreb () and Northwest Africa, is the western part of the Arab world. The region comprises western and central North Africa, including Algeria, Libya, Mauritania, Morocco, and Tunisia. The Maghreb al ...

region since the Early Holocene. Its diet was probably dominated by

grass Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and spe ...

, consistent with its classification as a grazer.

References

Dicerotini Pliocene mammals of Africa Pleistocene mammals of Africa Pliocene rhinoceroses Pleistocene rhinoceroses Fossil taxa described in 1888 Taxa named by Auguste Pomel {{paleo-oddtoedungulate-stub