The student is expected to: 7A analyze and evaluate how evidence of common ancestry among groups is provided by the fossil record, biogeography, and homologies, including anatomical, molecular, and developmental; 7B analyze and evaluate scientific explanations concerning any data of sudden appearance, stasis, and sequential nature of groups in the fossil record;

Continued: 8C compare characteristics of taxonomic groups, including archaea, bacteria, protists, fungi, plants, and animals; 10A describe the interactions that occur among systems that perform the functions of regulation, nutrient absorption, reproduction, and defense from injury or illness in animals

KEY CONCEPT Reptiles were the first amniotes.

Reptiles are a diverse group of amniotes. Reptiles share several characteristics. ectotherms covered with dry scales reproduce by laying or retaining amniotic eggs three-chambered heart cloaca

Reptiles have two reproductive strategies. Oviparous reptiles deposit eggs into an external nest. Viviparous reptiles retain eggs and give birth to live offspring.

Reptiles have been evolving for millions of years. Over time, amniotes evolved into three different groups. synapsids anapsids diapsids

The diversity of ancient reptiles led to the evolution of modern reptiles, birds, and mammals.

There are four modern groups of reptiles. Turtles, tortoises, and terrapins are the remaining anapsids. bony shell encases body 200 species

Sphenodonts are closely related to lizards. diapsids primitive characteristics two species

shed skin at regular intervals flexible skull Jacobson’s organ Snakes and lizards are very closely related and share a number of features. diapsids shed skin at regular intervals flexible skull Jacobson’s organ brain tongue Jacobson’s organ

Crocodilians are more closely related to birds than other diapsids. semi-aquatic predators 23 species