Presentation
• Turtles are reptiles, not amphibians (Reptiles include: turtles, crocodiles and birds, sqamalates (lizards and snakes)
• They are the oldest and most primitive of living reptiles; at least 200 million years old
• Sheels (carapace and plastron) unique in vertebrates
• Ectotherms seasonal activity cycle (April-October)
• High adult survivorship, can live almost as long as we do
• Low egg and juvenile survivorship
• Many populations are threatened
• Ectotherms: An organism whose body temperature is controlled by the outside environmental temperature
• Amphibians; moist or dry skin; no scales or claws
• Reptile has dry skin, scales and claws
• Turtles are remarkable
o The shoulder girdle and neck are inside the rib cage
o Some can live as long as humans
o Can live many days underwater without oxygen
o Can survive formonths underwater without respiratory breathing
o Can survive for months at temperatures near freezing; box turtles can actually freeze solid
o Females can store sperm for a year or more
o Can reproduce as senior citizens
o Gender of hatchlings is determined by incubation temperature, not by sex chromosomes
o Earliest turtles had teeth; now they just have beaks
o A common ancestor gave rise to lungfish, reptiles, mammals
o Slow development & unlimited growth
o Delayed sexual maturity
o No territoriality
o Variable clutch size
o Temperature-dependent gender determination
o No parental care “makes it easier if you are laying eggs your whole life”
o Hatchlings often “overwinter” in nest (survival adaptation—emerge at auspicious moment)
o Shell itself is bone
o Scutes—horny scales made of keratin--overlay bones and hold them together
o There are muscles attached to the hinge, as with bivalves, that contract when they are threatened and make them impossible to get into
o New England Turtles: about a dozen (excluding sea turtles)
o Threats
Habitat destruction
Cars
Increase in diseases (a rhonovirus has “jumped” from amphibians to box turtles, and it is very deadly
• Turtles are reptiles, not amphibians (Reptiles include: turtles, crocodiles and birds, sqamalates (lizards and snakes)
• They are the oldest and most primitive of living reptiles; at least 200 million years old
• Sheels (carapace and plastron) unique in vertebrates
• Ectotherms seasonal activity cycle (April-October)
• High adult survivorship, can live almost as long as we do
• Low egg and juvenile survivorship
• Many populations are threatened
• Ectotherms: An organism whose body temperature is controlled by the outside environmental temperature
• Amphibians; moist or dry skin; no scales or claws
• Reptile has dry skin, scales and claws
• Turtles are remarkable
o The shoulder girdle and neck are inside the rib cage
o Some can live as long as humans
o Can live many days underwater without oxygen
o Can survive formonths underwater without respiratory breathing
o Can survive for months at temperatures near freezing; box turtles can actually freeze solid
o Females can store sperm for a year or more
o Can reproduce as senior citizens
o Gender of hatchlings is determined by incubation temperature, not by sex chromosomes
o Earliest turtles had teeth; now they just have beaks
o A common ancestor gave rise to lungfish, reptiles, mammals
o Slow development & unlimited growth
o Delayed sexual maturity
o No territoriality
o Variable clutch size
o Temperature-dependent gender determination
o No parental care “makes it easier if you are laying eggs your whole life”
o Hatchlings often “overwinter” in nest (survival adaptation—emerge at auspicious moment)
o Shell itself is bone
o Scutes—horny scales made of keratin--overlay bones and hold them together
o There are muscles attached to the hinge, as with bivalves, that contract when they are threatened and make them impossible to get into
o New England Turtles: about a dozen (excluding sea turtles)
o Threats
Habitat destruction
Cars
Increase in diseases (a rhonovirus has “jumped” from amphibians to box turtles, and it is very deadly
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