Chp 34 part 2 Flashcards
What does amphibian mean?
Means “both ways of life,” referring to the metamorphosis of an aquatic larva into a terrestrial adult
What are tadpoles?
Herbivores that lack legs, but legs, lungs, external eardrums, and adaptations for carnivory may all arise during metamorphosis
Fertilization for amphibians
- Fertilization is external and require a moist environment
- In some species, male or females care for the eggs on their back, in their mouth, or in their stomach
What are the causes of amphibian decline?
- disease causing chytrid fungus
- habitat loss
-climate change - pollution
What are amniotes ?
Group of tetrapods who living members are reptiles, including birds, and mammals that have a terrestrially adapted egg
What is the amniotic egg?
A derived characteristic of amniotes in which the egg contains membranes that protect the embryo
What are the extraembryonic membranes in the amniotic egg? (4)
- Amnion
- Chorion
- Yolk Sac
- Allantois
What are other terrestrial adaptions of amniotes?
- Relatively impermeable skin
- Ability to use the rib cage to ventilate the lungs
What consists of the reptile clade? (7)
- Tuataras
- Lizards
- Snakes
- Turtles
- Crocodilians
- Birds
- Some extinct groups
What are most reptiles?
Ectothermic: Absorbing external heat as the main source of body heat
What are birds?
Endothermic: Capable of maintaining body temperature through metabolism
How do ectotherms regulate their body temp?
Thru behavioral adaptations
What are the first major group of reptiles?
Parareptiles: Large, stocky quadrupedal herbivores
What were the next group after parareptiles? What are the 2 main lineages of this group?
Next up were the diapsids.
2 lineages: Lepidosaurs and Archosaurs
What do lepidosaurs include?
- Tautaras
- Lizards
- Snakes
- Extinct Mososaurds
What do archosaurs consist of?
- Crocodilians
- Pterosaurs
- Dinosaurs
What were the first tetrapods to exhibit flight?
Pterosaurs
What does Pterosaurs include?
Includes bipedal carnivores called Theropods: group from which birds descended
What are characteristics of turtles?
- Boxlike shell made up of upper and lower shields
- Shell is fused to vertebrae, clavicle, and ribs
- Some adapted to land while others adapted to aquatic environments
What are the surviving lineage of Lepidosaurs?
Tuataras
Squamates
Lizards
Snakes
What are characteristics of snakes? (6)
- Has chemical sensors
- Heat detecting organs
- Venom
- Loosely articulated jawbones and elastic skin
- Carnivorous
- Legless lepidosaurs
Where are living crocodilians restricted to?
Restricted to warm regions
What are derived characteristics of birds? 6
- Had adaptations that facilitate flight
- Wings with keratin feathers
- Lack of urinary bladder
- Females with only one ovary
- Small gonads
- Loss of teeth
What is the oldest bird known?
Archaeopteryx
What clade does living birds belong to?
Neornithes
What group of birds are flightless? (3)
- Ratites (order Struthioniformes)
- Penguins (order Sphenisciformes)
- Certain species of rails, ducks, and pigeons
How can be bird species be distinguished? (6)
- Profile
- Color
- Flying style
- Behavior
- Beak shape
- Foot structure
What are mammals?
Amniotes that have hair and produce milk
What are the derived characteristics of mammals? (5)
- Mammary glands, which produce milk
- Hair
- A high metabolic rate, due to endothermy
- A larger brain than other vertebrates of equivalent size
-Differentiated teeth
What are synapsids?
Two bones that formerly made up the jaw joint were incorporated into the mammalian middle ear
In the early Cretaceous period, what 3 living lineages of mammals emerge?
- monotremes
- marsupials
- eutherians
What are monotremes?
- small group of egg-laying mammals consisting of echidnas and the platypus
What are marsupials? (3)
- opossums
kangaroos
koalas
Where does the marsupial embryo develop?
Develop within a placenta in the mother’s uterus.
What is a marsupium?
Maternal pouch of marsupials
What are eutherians?
Placental mammals that complete their embryonic development within a uterus that’s connected to the placenta
What does the mammalian order Primates include? (4)
- Lemurs
- Tarsiers
- Monkeys
- Apes –> Humans are apart of this
What are derived characteristics of primates? (6)
- Hands and feet adapted for grasping
- Flat nails
- large brain and short jaws
- Fully opposable thumb (monkeys and apes)
- Complex social behavior/parental care
- Forward looking eye close together for depth preception
What are the 3 main groups of living primates?
- lemurs, lorises, and bush babies
- Tarsiers
- Anthropoids –> Monkeys and apes
Are tarsiers more closely related to anthropoids or to lemurs?
Closely related to anthropoids
Which came first monkeys or apes?
Monkeys
What does the apes group consist of? (6)
- Gibbons
- Orangutans
- Gorillas
- Chimpanzees
- Bonobos
- Humans
What are humans?
Mammals that have a large brain and bipedal locomotion
What are derived characteristics of humans?
- Upright posture and bipedal locomotion
- Larger brains capable of language, symbolic thought, artistic expression, the manufacture and use of complex tools
- Reduced jawbones and jaw muscles
- Shorter digestive tract
How closely related are human and chimpanzee genomes?
99% closely related
What is paleonthropology?
Study of human origins
Are hominins (formerly known as hominids) more closely related to humans or chimpanzees?
Humans
What does early hominins show evidence of?
- small brains
- increasing bipedalism
What is one misconception of hominins? What is the correct fact?
Misconception: Early hominins were chimpanzees
Correction: Hominins and chimpanzees share a common ancestor
What is the second misconception of hominins? What is the correct fact?
Misconception: Human evolution is like a ladder leading directly to Homo sapiens
Correction: Hominin evolution included many branches or coexisting species, though only humans survive today
What are australopiths?
Paraphyletic assemblage of hominins
- some walked fully erect
Difference b/w Robust and Gracile Australopiths
Robust: Had sturdy skills and powerful jaws
Gracile: More slender and had lighter jaws
What does fossil evidence indicate about too use?
May have originated before the evolution of large brains
What are the Homo groups?
Homo habilis - Handy man
Homo ergaster -> First fully bipedal, large-brained hominid; decrease in sexual dimorphism (more difference b/w sexes)
Home erectus -> First hominin to leave Africa
Homo neanderthalensis
Homo sapiens
What are Neanderthals?
Ancestors of humans that were thick-boned with a large brain
- Buried their dead
- Made hunting tools
What are homo sapiens?
African ancestors of humans
all living humans are descended from here
What is the new found small hominin?
Homo floresiensis
Homo sapiens were the first group to show what?
Show evidence of symbolic and sophisticated thought