unit 1.4 Flashcards
To what group of mammal do whales belong?
Why was it so difficult to determine this?-
belong to cetaceamorpha group,
difficult to determine this because this group also includes dolphins and whales. Whales also belong to a group of organism commonly called ruminants (teradactula) which include hippos, pigs, camels, gazelles. The closest relative to whales are hippos.
What are whales their closest extant relatives?
their closest extant relatives are hippos
What was the diet of early whales? Be able to recognize the early whales and relatives (hint for some: Greek for whale)
-early whales where herbivores. Evolved to become carnivorous. Early whales and relatives in order: Indohyus, Pakicetus, Ambulocetus, Corudon, Basilosaurus, Modern Whales.
Be able to recognize bird synapomorphies:
feathers, beak, wings, forelimbs->turned into wings, hollow bones, endothermy, high metabolic rate, large heart, efficient respiratory system.
Why was a bipedal gait critical for the evolution of birds?
Bipedal dinosaurs evolved to have wings instead. Bipedal, no use for arms, led to gliders, led to wings
What are the three functions of feathers? When did feathers originate and what purpose did they serve?
Display
Thermoregulators
Flight
Early Feathers originated in therapy dinosaurs on head for display, then for thermal regulation, then for gliding
what about whales makes them distinct from other mammals
inner ear bones, have distinct inner ear bone that tells them apart from other mammals.
synapomorphies definition
a shared ancestor characteristic that all of the dependents still posses. feature unique to a group
a therapod dinosaur feature
had feathers, sign of feathers on all Dinos
Archeopteryx, Be able to recognize the ancestors and early birds (hint: Greek for wing and bird)
- Earliest bird: hunter, predator, lived in forests, large claws
- ave: bird
To what group of mammals do horses belong? What are the extant members of this group?
Horses belong and are relatives of Perissodactyla, extant members of group are tapears, rhinos, horses (all wild horses: (zebras, donkeys )and Domesticated horses)
What three trends do we see during the evolution of the horse lineage?
Teeth modification for grazing on grass, evolution of hoof, from 4 toes, to 3 toes, to 3 digits (only one of them was useful).
Teeth modification for grazing on grass, evolution of hoof, from 4 toes, to 3 toes, to 3 digits (only one of them was useful). and size
Be able to recognize the early horse species (hint: Greek for horse)
In order: phenacodus, odd-toed ungulates, eohippus, mesohippus, merchippus, piilohippus-> modern horses
Systematics
discipline of systematics include: phylogentics, taxonomy, classification
Phylogenetic
(relationships)dispicline of how organisms are closely related to one another. (Family tree)
Classification
finding those higher level things, grouping things into named groups.
Taxonomy
giving things names, species, gena, class, family
What do the different parts of phylogenetic trees represent: nodes, root, internal and terminal branches,
- Nodes-lines that come together, represent recent common ancestor
- Root- lowest branch coming out of phylogeny
- Internal branches-vertical: represent evolution, horizontal: space apart
- Terminal branches-names we put on end, represent a group or a single species
Hierarchical classification
group things into ever expanding groups (species->genus->family)
Tokogeny
family tree circles back, messy, inbreeding
What types of biological relationships would we expect to be tokogenous?
Inbreeding, mom is your cousin, your uncle married his sisters daughter
Taxon
name(species, class, genus)
Outgroup
is a close relative of whatever it is you are studying but it is distant
sister taxon-
group that is most closely related to each other
