Images of Sirenians, Sea Cows; Dugong and Manatee
by Sharon Mooney and Edward T. Babinski


  • Origin of Sirenians
    Earliest Sirenians, Prorastomus and Protosiren. Timeline of Sirenian Evolution and Extinctions. Images of the four extant manatee and dugong, and the extinct Steller's Seacow.
  • Sirenian Evolution: Elephant to Sea Cow
    Astonishing photographic evidence of similarities between modern sea cows and elephants. Including photographs with celebrity LeVar Burton from Reading Rainbow.
  • Sea Cows, Manatee and Sirenia Evolution
    Up close and personal with LeVar Burton and Manatees video. Photographs of Toenails on Manatee, and discussing diet, eating habits and lifestyle of Sea Cows.
  • Images of Sirenians
    All images illustrated by Sharon Mooney, available for download and public distribution for educational purposes.

    Sirenia are the order of placental mammals which comprise modern sea cows (manatee and dugongs) and their extinct relatives. They are the only herbivorous marine mammals now in existence and the only group of herbivorous mammals to have became completely aquatic. Sirenians have a 50 thousand year old fossil record (early Eocene-Recent). They attained modest diversity during the Ogliocene and Miocene, but have since declined as a result of climatic cooling, oceanographic changes, and human interference. Two genera and four species are extant: Trichechus which includes three species of Manatee that live along the Atlantic Coasts and in rivers and coastlines of the Americas and Western Africa. Amazonian Manatee live only in fresh water and Dugongs are found in the Indian and Pacific oceans.

    Library of Sirenian Images

    • Metaxytherium floridanum
    Metaxytherium Floradanum - Early Sirenian
    metaxytherium_floridanum2.jpg (500x143 - 19 K)
    metaxytherium_floridanum.jpg (750x215 - 40 K)
    Based on Encyclopedia of Marine Mammals
    Skeleton of Metaxytherium floridanum, a Miocene halitheriine dugongid. Total length about 3.2 meters. After Domning (1988); original image, Journal of Vertebrate Paleontology. Re-illustrated by Sharon Mooney, 2006.
    Public Access images may be redistributed, on condition all original credits are kept intact.     		Evolution in Sirenian Locomotion
    Evolution in Sirenian Locomotion
    sirenian_locomotion.gif (500x300 - 16 K)
    Based on Marine Mammals: Evolutionary Biology, Annalisa Berta, James L. Sumich
    Evolution in Sirenian Locomotion. Re-illustrated by Sharon Mooney, 2006
    Public Access images may be redistributed, on condition all original credits are kept intact.
    West Indian Manatee
    West Indian Manatee
    west_indian_manatee.jpg (500x204 - 19 K)
    Based on Sirenians of the World
    Re-illustrated by Sharon Mooney, 2006
    Public Access images may be redistributed, on condition all original credits are kept intact.     		West African Manatee
    West African Manatee
    west_african_manatee.jpg (500x248 - 23 K)
    Based on Sirenians of the World
    Re-illustrated by Sharon Mooney, 2006
    Public Access images may be redistributed, on condition all original credits are kept intact.
    Steller's Sea Cow
    Steller's Sea Cow
    stellers_sea_cow.jpg (500x158 - 16 K)
    Based on Sirenians of the World
    Re-illustrated by Sharon Mooney, 2006
    Public Access images may be redistributed, on condition all original credits are kept intact.     		Dugong
    Dugong
    dugong.jpg (500x191 - 16 K)
    Based on Sirenians of the World
    Re-illustrated by Sharon Mooney, 2006
    Public Access images may be redistributed, on condition all original credits are kept intact.
    Amazonian Manatee
    Amazonian Manatee
    amazonian_manatee.jpg (500x209 - 17 K)
    Based on Sirenians of the World
    Re-illustrated by Sharon Mooney, 2006
    Public Access images may be redistributed, on condition all original credits are kept intact.     		Sirenian Evolution Chart
    Sirenian Evolution Chart
    (Manatee, Dugong, Sea Cows)
    sirenians_evolution_graph.gif
    (500x881 - 46 K)
    Based on Encyclopedia of Marine Mammals
    Re-illustrated by Sharon Mooney, 2006
    Public Access images may be redistributed, on condition all original credits are kept intact.
    Sirenian Evolution Chart
    Protosiren Fraasi, 1906, Andrews
    protosiren_andrews_1906_750.jpg (750x814 - 149 K)
    protosiren_andrews_1906_500.jpg (500x542 - 73 K)
    protosiren_andrews_1906.jpg (860x933 - 201 K)
    Type specimen of Protosiren fraasi Abel as illustrated, 113 natural size, by Andrews (1906) [CGM 101711. Type is a nearly complete cranium shown here in A, ventral view; C, posterior view; and D, dorsal view. B shows worn surface of right I' tusk (crowns of left and right I' tusks are preserved as casts in NHML and UM replicas of the type made at the turn of the century, but they are no longer preserved in the original type). Reconstruction of premaxillary rostrum shown here is too long and straight (plaster reconstruction, now missing in original type, is shown with crosshatching). Andrews (1906) and Abel (1928) interpreted P4 or dp4 as having multiple roots, but Protosiren is now known to have retained both P4 and P' as single-rooted teeth.
    Based on Cranial Morphology of Protosiren fraasi, (Mammalia, Sirenia) from the Middle Eocene of Egypt: A New Study Using Computed Tomography
    Public Access images may be redistributed, on condition all original credits are kept intact.     		Protosiren Fraasi
    Protosiren Fraasi from Egypt
    protosiren_750_nolabels.jpg (750x445 - 52 K)
    protosiren_750_labels.jpg (750x445 - 61 K)
    protosiren_750_5_premolar.jpg (750x445 - 56 K)
    protosiren_500_nolabels.jpg (500x297 - 27 K)
    protosiren_500_labels.jpg (500x297 - 32 K)
    protosiren_500_5_premolar.jpg (500x297 - 29 K)
    New reconstruction of type skull of Protosirenfraasi, CGM 10171, with additions from SMNS 10576. Dentary is shown in outline, based on CGM 42297, which may be part of type specimen (see Andrews, 1906). Reproduced ca. 0.45 x natural size. Abbreviations (after Domning, 1978, with additions): AC, alisphenoid canal; AS, alisphenoid; c', upper canine alveolus; EO, exoccipital; FR, frontal; 1' etc., upper incisor alveoli; J, jugal; MI etc., lower molars; MF, mastoid foramen; MX, maxilla; OC, occipital condyle; P1 etc., upper premolar alveoli; PA, parietal; PM, premaxjlla; SO, supraoccipital; SQ, squamosal; SR, sigmoid ridge.
    Based on Cranial Morphology of Protosiren fraasi, (Mammalia, Sirenia) from the Middle Eocene of Egypt: A New Study Using Computed Tomography
    Re-illustrated by Sharon Mooney, 2006
    Public Access images may be redistributed, on condition all original credits are kept intact.
    Eotheroides aegyptiacum
    Eotheroides aegyptiacum
    eotheroides_aegyptiacum_702
    (702x988 - 132 K)
    eotheroides_aegyptiacum_500
    (500x704 - 72 K)
    Type specimen of Eotheroides aegyptiacum (Owen) as illustrated, natural size, by Owen (1875) [specimen is now catalogued as NHML 467221. Type is a natural stone endocast shown here in A, right lateral view; B, dorsal view; and C, ventral view. Abbreviations are as follows: a, "pons Varolii"; b, anterior myelonal columns; c, limit of posterior myelonal columns;f, falx cerebri; o, optic nerve; r, tramverse ridge separating impressions of basisphenoid and basioccipital; p, pedicle of pituitary body; R, rhinencephalon (olfactory bulb); tr, trigeminal nerves; v, upper vermiform process; x, lateral myelonal columns; 5, prominence anterior to sylvian fissure. Illustration and abbreviations reproduced from Owen (1875).
    Based on Cranial Morphology of Protosiren fraasi, (Mammalia, Sirenia) from the Middle Eocene of Egypt: A New Study Using Computed Tomography
    Public Access images may be redistributed, on condition all original credits are kept intact.     		Cranium of Protosiren fraasi
    Cranium of Protosiren fraasi
    protosiren_cranium_750.jpg (735x1024 - 106 K)
    protosiren_cranium_500.jpg (500x696 - 63 K)
    Cranium of Protosiren fraasi, A Dorsal, B left lateral, C palatal views
    Priem referred his dentary to the same taxon as Andrews' CGM 42297, possibly anticipating that it would look like CGM 42297 when fully adult. Then Priem, citing Abel (1904, 1906), called Andrews' specimen, and hence his own, Protosirenfrmi. Later Sickenberg (1934) considered Priem's dentary "probable" to represent P. fraasi and referred no other dentaries to this species (inexplicably ignoring CGM 42297). Thus small dentaries with very narrow symphyses have come to typify Protosiren (compare Domning et al., 1982, figs. 20, 21, and 34). However, specimens collected in Wadi Hitan (Zeuglodon Valley) in Egypt in recent years show that Protosiren there has a large dentary with large molars, and a wide mandibular rostrum with well-spaced alveoli for all anterior teeth Domning and Gingerich, 1994), while Eotheroides has the smaller dentary with smaller molars and a narrower rostrum (like Priem's dentary). Andrews was correct to place CGM 42297 in the same taxon as CGM 10171, and it might even be part of the type specimen (fide Andrews, 1906, p. 210). Both represent Protosiren fraasi.
    Based on Cranial Morphology of Protosiren fraasi, (Mammalia, Sirenia) from the Middle Eocene of Egypt: A New Study Using Computed Tomography
    Public Access images may be redistributed, on condition all original credits are kept intact.

    MORE LINKS ON SIRENIAN EVOLUTION

    Manatee Brain and Evolution of Manatees

    Univ. Florida Manatee Research Group

    Save the Manatee Club

    Sea World Education Department

    US Fish and Wildlife Search

    Vertebrate Animal Species Search

    Endangered Species Program

    Call of the Siren (An extensive website for sirenian researchers)

    Steller Seacow Page
    Steller's Seacow, natural history and skeletal elements in museums

    Rothauscher's Dugong Page
    Dugong, Natural history, distribution, etc.

    The Evolution of Whales

    The Fighting Natans

    RECOMMENDED READING

    The Emergence of Whales, J.G.M. Thewissen, PhD
    The Emergence of Whales    , Evolutionary Patterns in the Origin of Cetacea (Advances in Vertebrate Paleobiology) (Hardcover)
    by J. G. M. Thewissen (Editor)

    Review from Journal of Mammology, August 6, 2002
    Reviewer: Jasmine Benzvi (New York, NY)
    'Up to now, a 'state of the art' summary of research on whale origins has not been available. This book admirably fills that void and should be added to the library of any serious mammologist or paleomammalogist.'
    - by Annalisa Berta

    Encyclopedia of Marine Mammals
    Encyclopedia of Marine Mammals     (Hardcover)
    by William F. Perrin (Editor), Bernd Wursig (Editor), J.G.M. Thewissen (Editor)

  • "This impressive reference would make an excellent addition to any library..."-ENCYCLOPEDIA OF DINOSAURS AND VOLCANOES (February 2003)
  • "Very highly recommended for students, professionals, researchers and lay people with an interest in marine mammals." WILDLIFE ACTIVIST (Fall 2002)
  • "...an excellent resource for beginning research. ...This encyclopedia is very highly recommended for all academic and larger public libraries." Teresa Bowden, Villanova University Falvey Memorial Library for E-STREAMS (September 2002)
  • "...students beginning postgraduate study on marine mammals and researchers and academics working on marine mammals will find it indispensable."



    • Article last updated October 7, 2006
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