Living dinosaur

In cryptozoology, living dinosaurs are hypothetical non-bird dinosaurs that survived the Cretaceous-Tertiary extinction event and continue to exist today.

Living dinosaurs can also be used to denote Neornithes (modern birds), which are the only clade of dinosaurs to have survived the Cretaceous-Tertiary extinction event (apart from controversial reports of Paleocene dinosaurs). The term is also used for extinct species of dinosaurs that are claimed to exist today, a belief which is unsupported by scientific research.

Alleged living dinosaurs are typically based on interpretations of regional folklore, so their existence is often considered by the scientific community to be doubtful and merely the stuff of legend. Thus, reports of living dinosaurs can be studied as either being mythology, combined with a sociological phenomenon, or as possible evidence for further investigation in the field of cryptozoology.

The evidence advanced so far in support of dinosaur survival consists of interpretations of a variety of alleged eyewitness sightings, legends, and works of traditional art that, for some, supposedly depict dinosaurs. Such reports are problematic, as no physical evidence has been brought forth, and without such evidence it is difficult (if not impossible) to identify the animals in such reports as dinosaurs.

Reports

Most reports of allegedly surviving dinosaurs come from African rain forests in the Congo Basin and the rain forests of South America, although others include those from Australia and Scotland.

• Emela-ntouka, allegedly a living ceratopsian.
• Kasai rex, allegedly a living theropod.
• Mbielu-Mbielu-Mbielu, claimed to be a living stegosaur.
• Mokele-mbembe, claimed to be a living sauropod.
• Muhuru, allegedly a living ankylosaur.
• Nguma-monene, allegedly a living Spinosaurus.
• Ngoubou, allegedly a living Styracosaurus.

Other Mesozoic reptiles such as the winged pterosaurs have been reported as well.

• Kongamato, hypothesised to be a living Rhamphorhynchus.
• Mahamba, hypothesised to be a freshwater mosasaur.

Factuality

Living dinosaurs are often the subject of cryptozoological claims. However, paleontologists regard dinosaurs as having gone extinct at the Cretaceous-Tertiary extinction event, 65.5 million years ago,^[1][2][3][4] or, at most, a few hundred thousand years after, in the early Paleocene.^[5][6] There is no evidence that any non-avian dinosaurs survived beyond the Cretaceous,^[3][7] and there are strong arguments against the survival of populations of large dinosaurs. With no fossil evidence supporting the existence of Cenozoic dinosaurs, save for the few controversial discoveries limited to the early Paleocene,^[5][6] evolutionary scientists have not supported the existence of living dinosaurs.^[8] Reports of living dinosaurs can be studied in terms of cryptozoology, mythology and/or sociology, as in the work of Adrienne Mayor on how various cultures have interpreted fossils.

Still, some cryptozoologists^[who?] claim that living dinosaurs are zoologically possible, particularly in areas that have been geologically stable for the past sixty million years,^{[citation needed]} arguing that larger dinosaurs that are cold-blooded (ectothermic) might have a more successful chance thriving in stable, warm, equatorial regions than warm-blooded (endothermic) animals with higher metabolic rates.^{[citation needed]} However, it is not clear that any dinosaurs were ectothermic, and indeed the current scientific consensus is for high metabolic rates.^{[9][10][11][12]}

Areas that are often claimed to have been stable since the Cretaceous have changed considerably in that time.^{[citation needed]} At the end of the Cretaceous, Africa was significantly farther south than its current location and even small degrees of difference in location make for vastly different environments. The idea that dinosaurs (such as Mokèlé-mbèmbé) could have survived in the thick rainforests of the Congo, for instance, is not strictly supportable, since the Congo rainforests did not exist in anything like their present form, during the Cretaceous period. Similarly, many of Africa's major geological formations - the Great Rift Valley, for example - are much younger than the dinosaurs, having formed within the last 35 million years. The climate has also changed considerably in the last 20 thousand years. Most of the Congo Basin was semi-arid and covered with a dry-savanna vegetation. The rainforests had retreated to the extreme east (the highlands of Kivu in eastern DRC, near the border with Uganda and Rwanda), extreme west (the coastal areas of Cameroon, Gabon and Equatorial Guinea) and possibly also as narrow strips along some of the remaining major rivers. Hence, the rainforest and swamp vegetation in which these animals are now claimed to be found simply wasn't there until the rainforests spread across the Congo Basin again toward the end of the last ice age and after, around 12 thousand years ago.^{[citation needed]}

See also

• Lazarus taxon
• Living fossil
• Origin of birds
• Paleocene dinosaurs

References

1. ^ Glut, Donald F. (1997). Dinosaurs: The Encyclopedia. Jefferson, North Carolina: McFarland & Co. pp. 40. ISBN 0-89950-917-7. 
2. ^ Sullivan, Robert M. (2003). "No Paleocene Dinosaurs in the San Juan Basin, New Mexico". Geological Society of America Abstracts with Programs 35 (5): 15. http://gsa.confex.com/gsa/2003RM/finalprogram/abstract_47695.htm. Retrieved 2010-08-21. 
3. ^ ^{a b} Fastovsky, David E.; Sheehan, Peter M. (2005). "The Extinction of the Dinosaurs in North America". GSA Today 15: 11. doi:10.1130/1052-5173(2005)015<4:TEOTDI>2.0.CO;2. http://www.geosociety.org/gsatoday/archive/15/3/pdf/i1052-5173-15-3-4.pdf. Retrieved 2010-08-21. 
4. ^ Fastovsky, David E.; Sheehan, Peter M. (2005). "Reply to Comment on 'The Extinction of the Dinosaurs in North America'". GSA Today 15: 11. doi:10:1130/1052-5173(2005)015<11:TEOTDR>2.0.CO;2. http://www.geosociety.org/gsatoday/archive/15/7/pdf/i1052-5173-15-7-11b.pdf. Retrieved 2010-08-21. 
5. ^ ^{a b} Sloan, Robert E.; Rigby, Keith; Van Valen, Leigh M.; Gabriel, Diane (1986). "Gradual Dinosaur Extinction and Simultaneous Ungulate Radiation in the Hell Creek Formation". Science 232 (4750): 629–633. Bibcode 1986Sci...232..629S. doi:10.1126/science.232.4750.629. PMID 17781415. 
6. ^ ^{a b} Fassett, J.E.; Lucas, S.G.; Zielinski, R.A.; Budahn, J.R. (9–12 July 2000). "Compelling New Evidence for Paleocene Dinosaurs in the Ojo Alamo Sandstone, San Juan Basin, New Mexico and Colorado, USA". Catastrophic Events and Mass Extinctions: Impacts and Beyond, Vienna. http://www.lpi.usra.edu/meetings/impact2000/pdf/3139.pdf. Retrieved 2010-08-21. 
7. ^ Lucas, Spencer G. (2000). Dinosaurs: The Textbook (3rd ed.). Boston: McGraw-Hill. pp. 237. ISBN 0-07-303642-0. 
8. ^ Holtz, Thomas R., Jr. (2007). Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages. New York: Random House. pp. 363–364. ISBN 978-0-375-82419-7. 
9. ^ Bakker, Robert T. (1972). "Anatomical and Ecological Evidence of Endothermy in Dinosaurs". Nature 238 (5359): 81–85. Bibcode 1972Natur.238...81B. doi:10.1038/238081a0. 
10. ^ Fisher, Paul E.; Russell, Dale A.; Stoskopf, Michael K.; Barrick, Reese E.; Hammer, Michael; Kuzmitz, Andrew A. (2000). "Cardiovascular Evidence for an Intermediate or Higher Metabolic Rate in an Ornithischian Dinosaur". Science 288 (5465): 503−505. Bibcode 2000Sci...288..503F. doi:10.1126/science.288.5465.503. PMID 10775107. 
11. ^ Wedel, Mathew J. (2003). "Vertebral Pneumaticity, Air Sacs, and the Physiology of Sauropod Dinosaurs". Paleobiology 29: 243–255. doi:10.1666/0094-8373(2003)029<0243:VPASAT>2.0.CO;2. http://findarticles.com/p/articles/mi_qa4067/is_200304/ai_n9202774. 
12. ^ O'Connor, Patrick M.; Claessens, Leon P. A. M. (2005). "Basic Avian Pulmonary Design and Flow-Through Ventilation in Non-Avian Theropod Dinosaurs". Nature 436 (7048): 253–256. Bibcode 2005Natur.436..253O. doi:10.1038/nature03716. PMID 16015329. 

Bibliography

• Eberhart, George M. (2002). Mysterious Creatures: A Guide To Cryptozoology. ABC-CLIO, Inc. ISBN 1-57607-283-5.
• Ham, Ken (2000) Dinosaurs of Eden: A Biblical Journey Through Time. Master Books. ISBN 0-89051-340-6
• Hapgood, Charles (2000) Mystery in Acambaro: Did Dinosaurs Survive Until Recently?. Adventures Unlimited Press. ISBN 0-932813-76-3
• Shuker, Karl P. N. (1995) In Search of Prehistoric Survivors, Blandford, ISBN 0-7137-2469-2