Skip to main content

Protocetus








Protocetus


From Wikipedia, the free encyclopedia

Jump to navigation
Jump to search




















Protocetus
Temporal range: Middle Eocene

PreЄ

Є

O

S

D

C

P

T

J

K

Pg

N










Protocetus.jpg
Underside of a skull cast at the Museum für Naturkunde, Berlin

Scientific classification edit
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Artiodactyla
Infraorder:
Cetacea
Family:
Protocetidae
Genus:
Protocetus
Species:

P. atavus


Binomial name

Protocetus atavus
Fraas 1904

Protocetus atavus ("first whale") is an extinct species of primitive cetacean from Egypt. It lived during the middle Eocene period 45 million years ago.


The first discovered protocetid, Protocetus atavus was described by Fraas 1904 based on a cranium and a number of associated vertebrae and ribs found in middle Lutetian Tethyan marine limestone from Gebel Mokattam near Cairo, Egypt.[1]




Contents





  • 1 Description


  • 2 See also


  • 3 References

    • 3.1 Notes


    • 3.2 Sources





Description[edit]




Restoration


Protocetus had a streamlined, whale-like body around 2.5 metres (8.2 ft) long, but was relatively primitive in many respects; it still had small hind flippers, and its front flippers had webbed toes. Its jaws were long and lined with deadly teeth. The shape of the bones in the tails suggests that it may have evolved tail flukes, like those of modern whales, and, while it did not have a true blowhole, the nostrils had already begun to move backwards on the head.[2]


Unlike its more primitive predecessor Pakicetus, the structure of the ears suggests that Protocetus was able to hear properly underwater, although it is unlikely that it could echolocate. Similarly, it retained sufficient olfactory apparatus to have a good sense of smell, although it probably relied more on its eyesight to find prey.[2]



See also[edit]







  • Evolution of cetaceans


References[edit]



Notes[edit]




  1. ^ Bianucci & Gingerich 2011, p. 1174


  2. ^ ab Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 230. ISBN 1-84028-152-9..mw-parser-output cite.citationfont-style:inherit.mw-parser-output qquotes:"""""""'""'".mw-parser-output code.cs1-codecolor:inherit;background:inherit;border:inherit;padding:inherit.mw-parser-output .cs1-lock-free abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .cs1-lock-subscription abackground:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registrationcolor:#555.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration spanborder-bottom:1px dotted;cursor:help.mw-parser-output .cs1-hidden-errordisplay:none;font-size:100%.mw-parser-output .cs1-visible-errorfont-size:100%.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-formatfont-size:95%.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-leftpadding-left:0.2em.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-rightpadding-right:0.2em




Sources[edit]


.mw-parser-output .refbeginfont-size:90%;margin-bottom:0.5em.mw-parser-output .refbegin-hanging-indents>ullist-style-type:none;margin-left:0.mw-parser-output .refbegin-hanging-indents>ul>li,.mw-parser-output .refbegin-hanging-indents>dl>ddmargin-left:0;padding-left:3.2em;text-indent:-3.2em;list-style:none.mw-parser-output .refbegin-100font-size:100%


  • Fraas, Eberhard (1904). "Neue Zeuglodonten aus dem unteren Mitteleocän vom Mokattam bei Cairo". Geologische und Paläontologische Abhandlungen. Jena: Verlag Gustav Fischer. 6 (3): 199–220. Retrieved July 2013. Check date values in: |accessdate= (help)


  • Bianucci, Giovanni; Gingerich, Philip D. (2011). "Aegyptocetus tarfa, n. gen. et sp. (Mammalia, Cetacea), from the middle Eocene of Egypt: clinorhynchy, olfaction, and hearing in a protocetid whale" (PDF). Journal of Vertebrate Paleontology. 31 (6): 1173–1188. doi:10.1080/02724634.2011.607985. Retrieved September 2013. Check date values in: |accessdate= (help)










Retrieved from "https://en.wikipedia.org/w/index.php?title=Protocetus&oldid=831796821"





Navigation menu


























(window.RLQ=window.RLQ||).push(function()mw.config.set("wgPageParseReport":"limitreport":"cputime":"1.060","walltime":"1.370","ppvisitednodes":"value":30352,"limit":1000000,"ppgeneratednodes":"value":0,"limit":1500000,"postexpandincludesize":"value":215289,"limit":2097152,"templateargumentsize":"value":130200,"limit":2097152,"expansiondepth":"value":27,"limit":40,"expensivefunctioncount":"value":5,"limit":500,"unstrip-depth":"value":1,"limit":20,"unstrip-size":"value":6645,"limit":5000000,"entityaccesscount":"value":5,"limit":400,"timingprofile":["100.00% 1292.201 1 -total"," 68.43% 884.227 1 Template:Speciesbox"," 67.73% 875.240 1 Template:Taxobox/core"," 26.29% 339.657 76 Template:Period_start"," 19.05% 246.217 76 Template:Period_id"," 18.67% 241.285 2 Template:Phanerozoic_220px"," 17.03% 220.052 1 Template:Geological_range"," 16.15% 208.750 22 Template:Fossil_range/bar"," 15.12% 195.318 76 Template:MultiReplace"," 14.23% 183.892 1 Template:Fossil_range"],"scribunto":"limitreport-timeusage":"value":"0.646","limit":"10.000","limitreport-memusage":"value":6534772,"limit":52428800,"cachereport":"origin":"mw1271","timestamp":"20190108203446","ttl":1900800,"transientcontent":false);mw.config.set("wgBackendResponseTime":114,"wgHostname":"mw1326"););

Popular posts from this blog

马相伯

薛忠銘

各国军事列表