-
Reproduction on dry land
- 1. Gametes produced (and protected) in multicelluar structures called gametangia
- 2. Embryo retained and nourished by parent (mother) plant (embryophytes)
- 3. Desiccation-resistant spores; alternation of generations
- 4. Pollen!
-
Land plants practice a complex life cycle called
Alternation of Generations
-
pollen grain (n) is the
male gametophyte!
-
The same gametophyte produces both egg and sperm
Homosporous
-
heterosperms-
seeded, differnt gametophyte for egg and sperm
-
--------------- shares common ancestor with all Land Plants
Charophyceae
-
tracheid, then Vessel element
-
Redwood
Sequoia simpervirens
-
Seedless=
Seeded=
- homo
- hetero, male and female
-
-
Land plants appear: Fossil cuticle, spores, sporangia
Diversification of flowering plant
-
Animalia -
multicellular, heterotrophic eukaryans with tissues that develop from embryonic layers
-
Major animal features
- • No cell walls• Tissues (e.g., muscle, nervous)• Active movement• Sexual reproduction (haploid cells function directly—and only—as gametes)
- • Share unique embryonic development
-
mso-para-margin-right:0in;
- mso-para-margin-bottom:10.0pt;
- mso-para-margin-left:0in;
- line-height:115%;
- mso-pagination:widow-orphan;
- font-size:11.0pt;
- font-family:"Calibri","sans-serif";
- mso-ascii-font-family:Calibri;
- mso-ascii-theme-font:minor-latin;
- mso-hansi-font-family:Calibri;
- mso-hansi-theme-font:minor-latin;
- mso-bidi-font-family:"Times New Roman";
- mso-bidi-theme-font:minor-bidi;}
- amniote lineage with a single post-orbital opening on the skull
-
Early synapsids formed a group called
pelycosaurs
-
Therapsids:
the second major clade of nonmammalian synapsids
-
Mammalia
(4,500 species)• Hair• Mammary glands (lactation)• Three ossicles (bones) in middle ear• Single mandibular bone (dentary)
-
ear contains three ossicles (bones)
- 1. malleus
- 2. incus
- 3. stapes
-
Mammalia
(three major clades)
• Monotremata-eggs• Marsupiala- pouch• Eutheria- plecenta
-
-
Gametes produced (and protected) in multicelluar structures called
gametangia
-
-
three Ds of spores
Desiccation-resistance
Dormancy
Dispersal
-
placenta
formed from the allantois and chorion
-
Discuss the “terrestrial challenge” in light of vertebrates.
Supporting bodyweight, movement, exchange of respiratory gases, Preventing desiccation, reproduction
-
Frogs --------- (means without
tail)
order Anura
-
Lung less salamanders
Depend completely on skin and such
Salamander family Plethodontidae
-
Geckos
- climb with foot pads covered
- with specialized scales call setae (made of individual spatulae
- Clinging through van der Waals
- forces
-
Snakes-
- over 120 precaudal vertebrae
- Snakes are embedded phylogenetically
- within Lizards (aka specialized Lizards)
- Limb loss has evolved multiple times
- in many lizard lineages
-
o Forked tongue
allows snakes to sense their environment Chemosensory edge detector
-
o Crocodila
- Four-chambered heart (most
- sophisticated of any vertebrate)
- Parental care
- Dermal pressure receptors
- Saltwater crocodile-largest crocodile
-
Why does Archaeopteryx qualify as a
transition fossil?
- It’s thought to have been able to
- glide
-
List features that play an important role in bird flight.
- feathers
- Light weight skeleton
- Air sacs
- Organ reduction
-
The Pattern of Evolution
• Fossil record• Extinction• Transitional forms• Vestigial traits• Physiological change
-
Natural selection
sorts existing variants; it does not createor change them.
-
Dominant
recessive
codominant
- Dominant-A
- recessive-a
- codominant-A1A2
-
-
hardy winberg variables
- p= frequency of gene one
- q= frequency of gene two
- p2=A1A1
- 2pq=A1A2
- q2=A2A2
-
Hardy-Weinberg principle • Do allele frequencies and genotypicfrequencies change from one generation tothe next?
No!
-
The Hardy-Weinberg principle acts as
a null hypothesis when biologists want totest whether evolution or nonrandommating is occurring at a particular gene
-
From allelic frequencies we can compute
genotypic frequencies, and vice versa
-
What causes nonrandom mating?
- Inbreeding (mating between closely related individuals
- increases homozygosity in populations
sexual selection
-
1. prezygotic isolation
2. postzygotic isolation
- 1. prezygotic isolation(prevents mating or zygoteformation between
- species)2. postzygotic isolation(inviable or sterile offspring)
-
species with key innovaiton jaws
cichlid
|
|