BIOL 3300 Vertebrate Zoology: Ectotherms - Herpetology http://www.amphibian.com.au/
Why do herpetofauna need to exchange gases Why do herpetofauna need to exchange gases? What is needed to exchange gases?
What is needed to exchange gases? Ventilation = mechanical movement of fluids External respiration = environment to blood Cellular respiration = ? Internal respiration = blood to cytoplasm
How is oxygen gained/lost? Agalychnis callydryas http://www.ifrog.us/frog-facts/bizarre-facts/ What behaviors or adaptations are they exhibiting to influence rates?
How is oxygen gained/lost? Ambystoma tigrinum X What behaviors or adaptations are they exhibiting to influence rates?
Figure 6.19 Adaptive types of salamander larvae, or in some cases, paedotypic adults. Adapted from Duellman and Trueb, 1986.
How is oxygen gained/lost? Spea intermontana What behaviors or adaptations are they exhibiting to influence rates?
Figure 6.17 Longitudinal section through a tadpole, showing the placement of the internal gills beneath the operculum. Adapted from Viertel and Richter, 1999.
How is oxygen gained/lost? Gastrotheca cornuta (Marsupial Frog) What behaviors or adaptations are they exhibiting to influence rates?
Figure 6.18 Direct-developing young of the hylid frog Gastrotheca cornuta (Amphignathodontidae). Offspring develop in the dorsal pouch of the female, and oxygen diffuses from the female across the thin, bell-shaped gills of the froglet. Adapted from Duellman and Trueb, 1986.
How is oxygen gained/lost? Cryptobranchus alleganiensis http://news.nationalgeographic.com/news/2010/08/100820-hellbenders-snot-otters-sperm-amphibians-science-environment/ What behaviors or adaptations are they exhibiting to influence rates?
How is oxygen gained/lost? http://www.youtube.com/watch?v=j06d2CjolcI http://www.youtube.com/watch?v=C8CbKcAUM8k&feature=related http://www.arkive.org/titicaca-water-frog/telmatobius-culeus/video-10.html Telmatobius culeus What behaviors or adaptations are they exhibiting to influence rates?
Figure 6. 20 Cutaneous exchange of gases in amphibians and reptiles Figure 6.20 Cutaneous exchange of gases in amphibians and reptiles. Open bars indicate uptake of oxygen; shaded bars indicate excretion of carbon dioxide. Values represent the percent of total gas exchange occurring through the skin. Adapted from Kardong, 1995.
How is oxygen gained/lost? Plethodon idahoensis What behaviors or adaptations are they exhibiting to influence rates?
How is oxygen gained/lost? Pseudacris regilla What behaviors or adaptations are they exhibiting to influence rates?
How is oxygen gained/lost?
Figure 6. 23 Respiration in a frog Figure 6.23 Respiration in a frog. Oxygenated air is taken into the buccal cavity through the nares. Deoxygenated air in the lungs is rapidly expelled and does not mix with the air in the buccal cavity. Elevation of the buccal cavity (the buccal pump) forces the new air into the lungs. The glottis is then closed to hold the oxygenated air in the lungs, and the remaining air in the buccal cavity is expired by further elevation of the buccal cavity. Adapted from Withers, 1992.
Figure 6.24 Mean volume of erythrocytes decreases with increasing elevation in several frog species. Shaded circles are bufonids (originally reported as in the genus Bufo, now in the genera Duttaphrynus and Rhinella), open circles are Telmatobius (Ceratophryidae), and closed circles represent much earlier data from 22 anuran species in eight genera from Chile. Dashed polygons enclose data for bufonids and species of Telmatobius. Adapted from Navas and Chauí-Berlinck, 2007.