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UNDER CONSTRUCTION - Raw notes follow

Lecture 22 - Hot Blooded Dinosaurs II - Tracking Dinosaurs

II. GETTING AT METABOLISM FROM DINOSAURIAN

				STRUCTURAL PARALLELS


	A. NOW WE CAN SEE THAT DINOSAURS COULD PROBABLY

				RUN VERY FAST BUT SO CAN SOME REPTILE FOR

				SHORT DISTANCES


	B. STRUCTURALLY, HOWEVER, THEY ARE MAMMAL OR BIRD LIKE


		1. STRUTHIOMIMUS - OSTRICH 


		2. DEINONYCHUS - ARCHAEOPTERYX


		3. HADROSAUR - ELK


	C. LARGE ANIMALS HAVE SIMILAR STRCTURAL REQUIREMENTS



		1. SAUROPOD AND ELEPHANT


III. INTERNAL CONSTANCY VS VARIABILITY OF TEMP


	A. WHAT ABOUT HEAT PRODUCTION

	

	1. RESTING METABOLIC RATE GREATER IN MAMMALS

				AND BIRDS THAN IN REPTILES


			SLIDE OF RESTING METABOLIC RATE FROM MC A


		2. SIZE CONFERS SOME THERMAL INERTIA


			1. SURFACE AREA IS WHERE HEAT IS LOST


			2. SURFACE AREA INCREASES AS THE SQUARE OF linear DIM


			3. BUT VOLUME INCREASES AS THE CUBE


			4. THEREFORE FOR THINGS OF SIMILAR SHAPE,

						LARGE THINGS LOSE HEAT SLOWER


			5. BIG ANIMALS HAVE GREAT THERMAL INERTIA


				SO BIG DINOS WERE COULD HAVE BEEN INERTIAL

				HOMEOTHERMS


			SLIDE DATA ON LITTLE VS BIG TEMPS


		3. ALSO THIS MEANS THAT LARGE THINGS WITH

					HIGH METABOLIC RATES NEED TO DUMP HEAT


		4. BUT SMALL THINGS LIKE SHREWS NEED TO

					CONSERVE IT ALWAYS


		5. SOMETIMES BIRDS WITH GOOD INSULATION NEED

					TO COOL - AIR SAC SYSTEM


		6. AIR SAC SYSTEM PRESENT IN GIANT SAUROPODS

					- PROBABLY FOR COOLING


	B. OF COURSE, IF YOU HAVE HIGH METABOLIC RATES

				YOU NEED TO EAT MORE FOOD


			SLIDE OF BAKKERS DOG VS LIZARD PG 376


		1. THUS WE WOULD EXPECT THE SAME NUMBER OF PREY

					ANIMALS TO BE ABLE TO FEED A LARGE NUMBER OF

					LOW METABOLIC RATE ANIMALS THAN HIGH ONES


		2. IN FACT IF WE LOOK AT THE DISTRIBUTION OF

					PREDATOR-PREY RATIOS WE CAN SEE THAT DINOSAURS

					HAVE A LOWER PREDATORY/PREY RATIO THAN EOCENE MAMMALS


			SLIDE OF PREDATOR/PREY RATIOS DRAWING FROM BAK PG 351


		3. THUS IT EVIDENTLY TOOK MANY, MANY HERBIVOROUS

					DINOSAURS TO FEED ONE CARNIVOROUS ONES


IV. ACTIVITY LEVEL VS. BONE STRENGTH


	1. IT HAS LONG BEEN OBSERVED THAT THE STRUCTURE

				OF THE BONES IN MAMMALS AND BIRDS IS DIFFERENT

				THAN THAT SEEN IN OTHER LIVING REPTILES


		ADAPTED SLIDE FROM BAKKER PG 352


		HAVERSIAN SYSTEM PRESENT IN BIRDS AND MAMMALS


			EXPLAIN


		SLIDE OF HAVERSIAN SYSTEM AND NOT


			EXPLAIN CROMPTON'S ARGUMENT


V. PHYLOGENETICS


	SHARED DERIVED CHARACTERS OF DINOSAURS AND BIRDS


		FOUR CHAMBERED VS THREE CHAMBERED HEART


VII. SUMMARY


	A. DINOSAURS COULD RUN VERY FAST


	B. DINOSAURS WERE BUILT FOR LONG PERIODS OF ACTIVITY


	C. LARGE DINOSAURS COULD HAVE EASILY BEEN INERTIAL

				HOMEOTHERMS BUT SMALL ONES HAD TO PRODUCE EXTRA

				HEAT OR WOULD HAVE TO ADAPT THEIR BEHAVIOR TO

				RECEIVE IT FROM ENVIRONMENT


	D. LARGE DINOSAURS NEEDED TO LOSE HEAT


	E. PREDATOR/PREY RATIOS SUGGEST THAT CARNIVOROUS

				DINOSAURS NEEDED AS MUCH FOOD AS CARNIVOROUS MAMMALS


	F. DINOSAUR BONES REMODELED AS OFTEN AS MAMMAL AND

				BIRD BONE SUGGESTING HIGH ACTIVITY LEVELS


	G. BIRD ARE DINOSAURS AND MAY HAVE INHERITED THEIR

				METABOLIC SYSTEMS


	CONCLUSION: 	


				AT LEAST SOME DINOSAURS WERE AS ACTIVE AND

				"WARM BLOODED" AS ANY MAMMAL OR BIRD


	AND SO ALTHOUGH WE CANT GO BACK IN TIME AND

	MEASURE THEM WE CAN INFER, MAKE PREDICTION AND

	TEST THEM IN THE FOSSIL RECORD


NOTE THAT COMBINED WITH THEIR LOCOMOTOR ADAPTATIONS

IT BECOMES EASY TO SEE WHY DINOSAURS REMAINED

DOMINANT FOR SO LONG OVER MAMMALS






Dinosaur Sociality from Tracks

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