Mancallinae is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

of prehistoric flightless alcids that lived on the

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the cont ...

coast of today's

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

and

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

from the late

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 ...

epoch to the early

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

(ranging from at least 7.4 million to 470,000 years ago). They are sometimes collectively referred to as Lucas auks after the scientist who described the first

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), ...

, Frederic Augustus Lucas.

Description

They had

evolved Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...

along somewhat similar lines as the

great auk The great auk (''Pinguinus impennis''), also known as the penguin or garefowl, is an Extinction, extinct species of flightless bird, flightless auk, alcid that first appeared around 400,000 years ago and Bird extinction, became extinct in the ...

, their

North Atlantic The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for ...

ecological Ecology () is the natural science of the relationships among living organisms and their environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere levels. Ecology overlaps with the closely re ...

counterpart, but their decidedly stubbier wings were in some aspects more convergent with

penguin Penguins are a group of aquatic flightless birds from the family Spheniscidae () of the order Sphenisciformes (). They live almost exclusively in the Southern Hemisphere. Only one species, the Galápagos penguin, is equatorial, with a sm ...

s. Compared with the

subarctic The subarctic zone is a region in the Northern Hemisphere immediately south of the true Arctic, north of hemiboreal regions and covering much of Alaska, Canada, Iceland, the north of Fennoscandia, Northwestern Russia, Siberia, and the Cair ...

great auk, they were also smaller (''see also:''

Bergmann's Rule Bergmann's rule is an ecogeographical rule that states that, within a broadly distributed taxonomic clade, populations and species of larger size are found in colder environments, while populations and species of smaller size are found in warmer ...

): ''Praemancalla'' species have been estimated to have weighed about 3 kg. Most ''Mancalla'' forms weighed somewhat less (about 2.4 kg), with ''M. milleri'' being a smaller (1.65 kg) and ''M. emlongi'' a much larger bird (3.8 kg) than the rest. The last species thus stood around 55–60 cm high in life. The largest species, ''Miomancalla howardi'', was the largest charadriiforme of all time.Smith, N. 2015. Evolution of body mass in the Pan-Alcidae (Aves, Charadriiformes): the effects of combining neontological and paleontological data. Paleobiology. doi: 10.1017/pab.2015.24

Evolution and classification

In a 2011 paper, N. Adam Smith published a review and revision of the Mancallinae. Smith defined Mancallinae as the

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

containing ''Mancalla'', ''Miomancalla'', their common ancestor and all its descendants. A summary of his results follows. *Pan-

Alcidae Auks or alcids are birds of the family Alcidae in the order Charadriiformes. The alcid family includes the murres, guillemots, auklets, puffins, and murrelets. The family contains 25 extant or recently extinct species that are divided into ...

Smith, 2011 **Mancallinae L.Miller, 1946 ***''

Mancalla ''Mancalla'' is an extinct genus of prehistoric flightless alcids that lived on the Pacific coast of today's California and Mexico during the Late Miocene to Early Pliocene Early may refer to: Places in the United States * Early, Iowa, a cit ...

'' Lucas, 1901 ****''Mancalla californiensis'' Lucas, 1901 ****''Mancalla cedrosensis'' Howard, 1971 ****''Mancalla lucasi'' Smith, 2011 ****''Mancalla vegrandis'' Smith, 2011 ***'' Miomancalla'' Smith, 2011 ****''Miomancalla howardi'' (Smith, 2011) ****''Miomancalla wetmorei'' (Howard, 1976) The following species could not be identified as unquestionable mancallines, and have been assigned to Pan-Alcidae ''incertae sedis''. They may be mancallines, or more closely related to true

auk Auks or alcids are birds of the family Alcidae in the order Charadriiformes. The alcid family includes the Uria, murres, guillemots, Aethia, auklets, puffins, and Brachyramphus, murrelets. The family contains 25 extant or recently extinct speci ...

s. *''Alcodes ulnulus'' Howard, 1968 *''Mancalla diegensis'' Miller, 1937 *''Mancalla milleri'' Howard, 1970 The following species could not be differentiated from other recognized species of mancallines (see above), and have been assigned to Mancallinae ''incertae sedis''. *''Mancalla emlongi'' Olson, 1981 *''Praemancalla lagunensis'' Howard, 1966 The mancallines probably evolved from proto-

puffin Puffins are any of three species of small alcids (auks) in the bird genus ''Fratercula''. These are pelagic seabirds that feed primarily by diving in the water. They breed in large colonies on coastal cliffs or offshore islands, nesting in crev ...

s, which must have been birds not dissimilar to the rhinoceros auklet. Accordingly, their status as a subfamily has been questioned as this would make the Alcinae (true auks)

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

. However, the mancallines were a very distinct and unique evolutionary lineage and are thus usually retained as a subfamily. They must have diverged from flying ancestors during the mid-Miocene, roughly 15 mya. ''Alcodes'' is known from a single

ulna The ulna or ulnar bone (: ulnae or ulnas) is a long bone in the forearm stretching from the elbow to the wrist. It is on the same side of the forearm as the little finger, running parallel to the Radius (bone), radius, the forearm's other long ...

found in Late Miocene (

Clarendonian The Clarendonian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 13,600,000 to 9,000,000 years BP, a period of . It is us ...

, 9–12 mya) deposits at Laguna Hills,

. While assignment of such a fragmentary fossil is always problematical, the ulna is a fairly distinctive bone and that of ''Alcodes'' is quite peculiar. However, it is more allied with the Mancallines as a matter of convenience; additional material would be needed to confirm this relationship. From the bone's measurements, it seems probable that this species was flightless and judging from its age, it either represents an earlier development parallelling ''Mancalla'', or a third lineage of flightless auks. ''Praemancalla'' is known from Clarendonian to Early

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

evolved from one of the two known species. ''Mancalla'' was a common species throughout the Pliocene, appearing in the

Hemphillian The Hemphillian North American Stage on the geologic timescale is a North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 10,300,000 to 4,900,000 years BP. It is usually considered t ...

stage of the Late Miocene (5–9 mya), and spreading in the Pliocene, with 4 species apparently coexisting at one time on the coast of southern California. As with many marine birds, the mancalline auks were much affected by the extinction crisis in the late Pliocene oceans. This coincided with the diversification of

marine mammals Marine mammals are mammals that rely on marine ecosystems for their existence. They include animals such as cetaceans, pinnipeds, sirenians, sea otters and polar bears. They are an informal group, unified only by their reliance on marine env ...

, but may ultimately have been caused by increased

supernova A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last stellar evolution, evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion ...

activity in the vicinity of the

Solar System The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Sola ...

. Despite their apparent awkwardness, they seem to have been quite well adapted for flightless birds, with the fossil record suggesting that the last remnants did not disappear until the Early Pleistocene, some time after the ecological changes had passed their peak.

References

{{Taxonbar, from=Q3285302 Auks Extinct flightless birds Neogene birds Bird subfamilies