LAB 10 - Animal Evolution Flashcards
What are examples of amphibians?
-frogs, toads, salamanders, newts, caecelians
What are examples of chondrichthyes?
-sharks, rays, skates + ratfishes (cartilaginous fish)
What is the common ancestor of both Amphibia and Chrondrichthyes?
Deuterostome
What is an example of Petromyzontida?
Lampreys
What are examples of Osteichthyes?
-trout, salmon, tuna (bony fish)
What are examples of Reptillia?
-snakes, turtles, lizards, crocodiles, birds
What are examples of Mammalia?
-cats, bats, whales, humans
What is the subphylum that includes both Amphibia and Chondrichtyes?
Vertebrata
What are 5 main characteristics of Chordates?
- dorsal notochord
- dorsal, hollow nerve cord
- pharyngeal gill slits
- post anal tail
- losing some characteristics as adults
What replaces the embryonic notocord?
vertebral column
_____ chambered heart. Open or closed?
- 2, 3, or 4 chambered heart
- closed circulatory system
What do the eyes of a chordate have?
lens and retina
How many pairs of appendages do chordates have?
2 pairs of appendages
What are the 2 organisms dissected in lab?
- Squalus acanthias (Chondrichtyes)
2. Rana catesbeiana (Amphibia)
Chondrichtyes characteristics (7)
- jawed fish with paired fins
- skeletons made of cartilage
- thick skin + placoid dermal scales
- spiracles (breathing when asleep
- carnivores (bottom feeders)
- ectotherms (cold-blooded animals
- internal fertilization
What are 4 characteristics of a Spiny dogfish?
- dorsal spines (toxic)
- no anal fin
- white spots along its back
- lateral line
How many gill slits do Spiny Dogfish have?
5
What is a spiracle?
vestigial 1st gill slit
What kind of heart does a Spiny Dogfish have?
2-chambered heart (A&V)
What kind of liver do Spiny Dogfish Sharks have?
oil-filled liver for buoyancy
What kind of intestines do Spiny Dogfish Sharks have?
spiral valve in intestines (increases absorption)
What kind of fertilization do spiny dogfish have?
internal
What kind of animal are Spiny Dogfish?
ovoviviparous
Where did Amphibian ancestors evolve from?
lobe-finned fishes called Coelacanths
What are 4 advantages of life on land?
- little competition
- absence of predators
- abundance of plants + insects
- high O2
What are 3 characteristics of amphibia?
- long hind legs
- short body
- webbed digits
What kind of lifestyle do amphibia have?
semi-aquatic lifestyle
What kind of reproduction do amphibia have?
- lay eggs in puddles, ponds or lakes
- external fertilization
What is an aquatic larval stage?
- tadpoles
- have gills and tails
What do amphibia eat? (3)
- arthropods
- annelids
- gastropods
What kind of animals are amphibia?
ectothermic animals
