Term
| Archaeopteryx lithographica |
|
Definition
means ancient wing
135-155 myo (Jurassic)
mosaic of bird and reptile features: primary +sec feathers, wing claws, teeth, bony tail |
|
|
Term
|
Definition
Thomas Huxley
-used Archaeopteryx as missing link to support evolution of birds as reptiles
Compsognathus- theropod dino |
|
|
Term
|
Definition
arboreal thecodont reptile with elongated scales
seemed to resemble feathers but NOT |
|
|
Term
|
Definition
rejected theropod link
dominated for 40 years
slow accumulation of evidence for clavicles of dinos
-Heilmanns fatal objection to theropod theory gone
theropod-bird link reborn in 1974 |
|
|
Term
|
Definition
Yale
series of papers showing derived shared characteristics of birds and theropod dinos |
|
|
Term
|
Definition
16 shared features between Deinonychus and birds
-wishbone
-hollow bones
-half moon shaped wristbone |
|
|
Term
|
Definition
| thinks its an embarrassment to associate birds and dinos |
|
|
Term
|
Definition
| Arboreal vs Cursorial hypothesis |
|
|
Term
|
Definition
terrestrial reptile
takes to trees
leaps between trees
eventually GLIDING
eventually Archaeopteryx (flapping flight) |
|
|
Term
| Pros and Cons to Arboreal |
|
Definition
Pros: many extant animals glide, gliding works
Cons: no examples of transition from gliding to powered flight (bats??). all extant gliders are quadrupeds (snakes w/o legs) |
|
|
Term
|
Definition
flight evolved from terrestrial running reptile
initially forelimbs elongated to catch prey
wings and tail not initially for flight but stability (modification to flight) |
|
|
Term
|
Definition
Pros:
1. protobirds would enjoy both kinds
2. cursorial consistent w/ precocial extant forms (bipedal habits of fossil dinos)
3. lift thrust vectors of early forms would have been directed to substrate (wings adapted to tackle steeper and steeper slopes, preadapted for aerial flight, gradual transformation to flight, not a big gap) |
|
|
Term
|
Definition
W.A.I.R. Theory might explain weird tiny wing and tail tufts
(french poodle wannabe dinos like Caudopteryx) |
|
|
Term
| Natural Selection shapes Bird Variation |
|
Definition
IF:
1. phenotypic variation
2. variation is heritable
3. phenotypic variation has fitness consequences (survival or reproduction)
THEN:
-will get evolutionary response; i.e. change in genes and phenotypes |
|
|
Term
|
Definition
used to study natural selection
-color band entire population for individual recognition
-measure traits such as beak and body
-follow survival & breeding of each individual
-band babies in nest, recapture and measure as adults |
|
|
Term
|
Definition
traits are polygenic- many genes
-cannot do Mendelian genetics
-use formal heritability
-strength of relation btwn parent and offspring indicates amount phenotypic variation due to genes
-most traits highly heritable in finches |
|
|
Term
| Does phenotypic variation affect performance? |
|
Definition
Yes.
1976 normal year vs 1977 drought year
-drought affected survival, and survivors were not a random subset of population
-massive die off during drought from 1400 down to 200 birds
NON RANDOM SURVIVAL: deeper beaks more likely to survive drought because FOOD supply changed due to climate change |
|
|
Term
| Biological Species Concept |
|
Definition
| groups of interbreeding natural populations that are reproductively isolated (very low gene flow) |
|
|
Term
|
Definition
| figuring out evolutionary relationships btwn taxa (trees) and forming monophyletic groups |
|
|
Term
|
Definition
classification (into bins)
Linnean system of Class (Aves), Order, Family, Genus, Species. |
|
|
Term
|
Definition
Cladistics (clades)
-shared derived characteristics (from DNA and morphology)
-convergent evolution can lead you astray
-based on parsimony |
|
|
Term
|
Definition
can hybridize DNA from different species
-heat to disassociate strands
-temp at melting indicates degree of DNA similarity
-lower melting temp, the more dissimilar the DNA is (more base pair differences)
-can use this as a quantitative measure |
|
|
Term
|
Definition
opposite birds
-fusion pattern in foot is opposite to modern birds |
|
|
Term
|
Definition
Hesperornis (toothed seabird)
-cormorant/loon type |
|
|
