[dinosaur] Dinosaur brain cooling strategies from blood vessel clusters

Ben Creisler
[email protected]

A new paper:

Wm. Ruger Porter  & Lawrence M. Witmer (2019)
Vascular Patterns in the Heads of Dinosaurs: Evidence for Blood Vessels,
Sites of Thermal Exchange, and Their Role in Physiological Thermoregulatory
Strategies.
The Anatomical Record (advance online publication)
doi:  https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.1002_ar.24234&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=bqTU-CajID3eytRf4btPh365meLY4ht5aHVMULudn3I&s=k-iH-BMNmZ_ME4-BlnPKqECS6JWmB7gUKUJ3GGeSw-Y&e= 
https://urldefense.proofpoint.com/v2/url?u=https-3A__anatomypubs.onlinelibrary.wiley.com_doi_abs_10.1002_ar.24234&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=bqTU-CajID3eytRf4btPh365meLY4ht5aHVMULudn3I&s=DUaOf25vCw5umdmuij30NIOSQPhQBEsTC4ZpCEK4ShE&e= 


Body size has thermal repercussions that impact physiology. Large‐bodied
dinosaurs potentially retained heat to the point of reaching dangerous
levels, whereas small dinosaurs shed heat relatively easily. Elevated body
temperatures are known to have an adverse influence on neurosensory tissues
and require physiological mechanisms for selective brain and eye
temperature regulation. Vascular osteological correlates in fossil dinosaur
skulls from multiple clades representing different body‐size classes were
identified and compared. Neurovascular canals were identified that
differentiate thermoregulatory strategies involving three sites of
evaporative cooling that are known in extant diapsids to function in
selective brain temperature regulation. Small dinosaurs showed similarly
sized canals, reflecting a plesiomorphic balanced pattern of blood supply
and a distributed thermoregulatory strategy with little evidence of
enhancement of any sites of thermal exchange. Large dinosaurs, however,
showed a more unbalanced vascular pattern whereby certain sites of thermal
exchange were emphasized for enhanced blood flow, reflecting a more focused
thermal strategy. A quantitative, statistical analysis of canal
cross‐sectional area was conducted to test these anatomical results,
confirming that large‐bodied, and often large‐headed, species showed
focused thermal strategies with enhanced collateral blood flow to certain
sites of heat exchange. Large theropods showed evidence for a plesiomorphic
balanced blood flow pattern, yet evidence for vascularization of the large
antorbital paranasal air sinus indicates theropods may have had a fourth
site of heat exchange as part of a novel focused thermoregulatory strategy.
Evidence presented here for differing thermoregulatory strategies based on
size and phylogeny helps refine our knowledge of dinosaur physiology.


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News:

Video:
Dinosaur brain cooling strategies - Theropod ventilation of vascularized
air sinus

https://urldefense.proofpoint.com/v2/url?u=https-3A__www.youtube.com_watch-3Fv-3DE1h6rJWtngg&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=bqTU-CajID3eytRf4btPh365meLY4ht5aHVMULudn3I&s=RDTWieBfbE_PpNEOp6UJPLMrPWwzfOIb2HWFb0E26x4&e= 

***

Big dinosaurs kept cool thanks to blood vessel clusters in their heads

https://urldefense.proofpoint.com/v2/url?u=https-3A__phys.org_news_2019-2D10-2Dhuge-2Ddinosaurs-2Devolved-2Dcooling-2Dcombat.html&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=bqTU-CajID3eytRf4btPh365meLY4ht5aHVMULudn3I&s=FFog60aBghlQvZXD4232PYNIthQdIcitlpnfSkFuHW4&e= 

https://urldefense.proofpoint.com/v2/url?u=https-3A__www.sciencenews.org_article_dinosaurs-2Dthermoregulation-2Dblood-2Dvessels-2Dhead&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=bqTU-CajID3eytRf4btPh365meLY4ht5aHVMULudn3I&s=scVI3RBVhEUYCDYhp9EvshTqOAhKr9qMI0qhrpwYe_g&e= 

https://urldefense.proofpoint.com/v2/url?u=https-3A__www.ohio.edu_news_2019_10_new-2Dohio-2Dstudy-2Dshows-2Dhuge-2Ddinosaurs-2Devolved-2Ddifferent-2Dcooling-2Dsystems-2Dcombat-2Dheat&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=bqTU-CajID3eytRf4btPh365meLY4ht5aHVMULudn3I&s=ZTpAOeboRduJcXscXiZxJ4-jwvpuZRxhZUZ5D-T_bFo&e= 


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