Niche
job role, function that an organism takes in an environment
Extinction
animals will change to fit empty roles
Mass extinctions cause
mass change in behavior
R-selective
many young
very little parental care
generalists tendency
ex: weeds
R-selective are
more likely to survive a mass extinction
K-selective
few young
more parental care
more specific
Ecological selection after a mass extinction
1st colonization→ R selective → K selective
Adaptive radiation
opens niches; adapt/occupy them
often with founders affect; need for niche fulfillment
Nicholas Steno
older fossils are simple at the bottom
younger fossils are complex at the top
Radio isotopes
undergo radioactive decay
addition of neutrons
1/2 life
lose 1/2 of radioactivity
Continental Drift
the plates experience rifts and divergence
plates float on a liquid mantle
During the continental drift there is a
redistribution of air/water flow, temperature, and humidity
Coreolis Effect
result of spinning
everything spins on the equator
Precambrian Era
pro-karyote→ eukaryotes → colony, specialized tissue
Eukaryotes
nucleated cells
much bigger
Cyanobacteria
no O2 → higher O2
photosynthetic bacteria (nutrients from light)
planet needed to be oxidized for free oxygen
oxygen was toxic; makes toxic by-products
O2 radical (O2.-)
picks up an extra electron and wants to give it away
bounce around; creates mutation
Anti-O2 radical (O2.-)
make ATP
neutralizes oxygen; detoxifies it
provides the energy to get big
Paleozoic Era Cambrian Period
all animal phyla increased
more phyla than present day due to mass extinction
Photosynthetic eukaryotes
can occur because O2 levels are high and O3 zones are accumulated
O3 (ozone)
protects from UV rays
Paleozoic Era Ordovician Period
marine diversity
mass extinction (lost 75%)
result of glacierization (decrease of sea level)
Volcanic activity
air→ particulates to the sulfur
reflects heat away
Paleozoic Era Silurian Period
H2O jawless fish→ jawed fish
colonization → land
nonvascular plants → vascular plants
enough O3 (arthropods and insects appear)
Paleozoic Era Devonian Period
larger insects
more insects
some animals
fish→ amphibians (vertebrates with lobed fins)
75% extinction
meteorite hit
Paleozoic Era Carboniferous Period
coal deposits
ferns dominated (large forests, humid/swampy environment")
big amphibians→ reptiles
cooling at the end
Paleozoic Era Permian Period
reptile diversity
95% of planet goes extinct
50% more oxygen here than present day
Permian burp
Permian Burp
more gas pressure than water lid pressure
the bottom rotting organic matter gas escapes the water
CH2 and CO2
organic snow: everything above that dies; decays and flaked in water
Mesozoic Era Triassic Period
lots of room for niche filling
develop early dinosaurs (better at adaptive radiation)
occupy empty niches
first mammals occur/ some flowering plants (not many)
conifer plants dominated (gymnosperms- evergreens)
herbivore dinosaurs ate
Mesozoic Era Jurassic Period
dinosaurs increased diversity
fish also went through major diversity stage
continents split, opened up more fish niches
Mesozoic Era Cretaceous Period
super advanced dinosaurs
sophistication (modifications)
increase flowering plants (angiosperms)
changes diet for dinosaurs
mammals presence is greater
diversify a little more
Yucatan Meteorite Strikes
Yucatan Meteorite Strike
75% mass extinction
Cenozoic Era Tertiary Period
any dinosaurs that survived the strike became birds
mammals made it through
occupy niches left
flowering plants make it
begin to diversify
insect diversify increases due to pollination
Cenozoic Era Quaternary Period
glaciation events (numerous)
large mammals start to go extinct
hominids → Homo sapiens
frees up hands (easy manipulation) HUGE SPECIATION EVENT
Animals are
multicellular; not a colony
cells have a relationship (organization)
tissues
heterotrophs
food from a source and break it down
homeostasis= constant internal environment
most animals have motion
particular developmental patterns
specific way an animals grows
2 embryonic tissues
diploblastic
ectoderm
endoderm
3 embryonic tissues
triploblastic
ectoderm
mesoderm
endoderm
Ectoderm
epidermis and nervous system
outside layer
Mesoderm
muscle, bone, cardiovascular system, kidney, renal system
Endoderm
form GI tract, form respiratory system, and glands
Layer formation
zygote→ morula→ blastocyst
Morula
solid mass
Blastocyst
cells are undifferentiated
gastrulation
pushing your hand into a beachball (invaginate)
protostome: mouth first
deuterostome: anus first
Symmetry
radial
bilateral
cephalization: sensory information and processor on one end
have a brain
Acoelomate
solid mesoderm
Pseudocoelomate
one sided mesoderm
Coelomate
split mesoderm
Heterotrophs
filter feeders: trap food from air or water
sponge: sessile (settled in one spot)
whale (not sessile): baleen (modified teeth)
Herbivores
plant eaters→ cellulose
animals don’t break down cellulose
must break down cellulose
multi chambered sweatpants
eat lots of plants (abundance)
eat w/o killing the plant
eat strategically so the plant can grow back
Predators
kill and eat something else
have morphology to capture and kill prey
DANGER: animals fight back
Parasite
harm to host (can modify behaviors)
must evade host immune system (self vs. non self cell)
Reproduction
hermaphrodite: male + female
produce lots of offspring
lay lots of eggs
Endoparasite
inside the host
ascaris (flatworm): crawl into parts of the body
Ectoparasite
outside the host
leech, flea
Intermediate hosts
host juvenile form of parasite
not the final stage for the parasite
Detritovore
aid in decay and breaking down of matter
get rid of dead and decaying matter
ex. earthworms
Diploblasts (2 layers; endoderm and ectoderm)
3 phyla
Porifera: sponges
Placozoa: found in deepwater trenches
have an endoderm and an ectoderm
also have fused cells (multi-nucleated)
Cnidaria: jellys, corals, sea anemones
Phyla Porifera
sponges and they are diploblastic (edo and ecto derm)
not colonial, have distinct tissues
can be broken apart, find each other again: reassemble
Simplest sponge
sessile
filter feeder (have pores)
choanocytes (endoderm)
pull water in (gastrovascular cavity)
filter feed
ostium (mouth)
Amoeboid cells
undifferentiated
distribute food
change into another cell
turn into gametes (sexual reproduction)
bud (asexual)- good living conditions
Spicule
some are calcium/ some are silicon (glass)
can break skin
Phyla Cnidaria
2 way gastrovascular cavities
Cnidocytes (cell)
stinging cells
Nematocyst
will burst if triggered (touched, chemicals)
sends out sticky/barbed filament
releases a toxin
Medula and Polyp stage
Cnidaria life cycle
polyp stage→ colony bud→ medusa stage →planula
Phyla Cnidaria- Class Scyphozoa
sperm and egg→ planula→ polyp (bud and strobula)→ medusa (ephrya)→ adult jellyfish
have to be able to coordinate
have a neural network/ nerve net
can be photosensitive
ocelli: eyespots (light for dark)
move towards or away from light
Class hydrozoa
polyp dominant
have a medusa stage for reproduction
budding medusa→ planula→ polyp
gastrozoid: catch food
have tentacles to trap and pull into GVC
gonadozoid/gonozad: reproduce (budding medusa)
Class anthozoa (sea anemones and coral)
all coral, no real medusa stage
sea anemones
tentacles
Acontia: internal tentacles that have stinging cells to kill food if it is not dead in the GVC
Coral
calcium carbonate base
symbiotic relationship with algae (zooxanthella)
dies when bleached
Phyla Placozoa
found in deepwater trenches
links porifera and cnidarians
flat-worm like
planula
Have an:
ectoderm: flagellated
syncytium
endoderm: glandular cells (have vesicles)
Syncytium
one large cell with lots of nucleotides; multinuclear large cell (slime mold)
causes question as to whether or not a placozoa is diploblastic
Triploblasts
ectoderm, mesoderm, endoderm
Protostomes or deuterostomes
Protostomes
form mouth first
Lophotrochozoans
skeleton grows by adding to it
Ecydozoans
molting exoskeleton (made of chitin)
Deuterostomes
form anus first
Phyla Platyhelminthes
acoelomates (absent body cavity)
solid mesoderm (depends on gas exchange)
brains are a cluster of ganglia
ladder-like nerve networks
eyespots= ocelli
chemoreceptors
flame cells
Platyhelminthes are flat
so they can handle simple diffusion
Brain in Platyhelminthes
brain: cluster of ganglia
nerves; not a true brain
on one end of the body; cephalization
ladder-like nerve network
2 spinal nerves coming down
communicating nerves
eyespots are ocelli
chemoreceptors: special sensory around the brain
Platyhelminthes shape and function
flat so they can handle simple diffusion
flame cells: get rid of waste
filter everything; put back what they need
beginning of a kidney
typically hermaphrodites
testis and ovaries in one worm
Phyla Platyhelminthes Class Turbellarian
free living flatworms (planaria)
Phyla Platyhelminthes Class Trematoda
flukeworms (parasitic)
ectoparasites
endoparasites
suckers/hooks
attach themselves to host
egg hatches→ intermediate hosts (snail)
Juvenile forms
fish
animals
clams
Phyla Platyhelminthes Class Cestoda
tapeworms
No gastrovascular cavity
live in GI tract
take nutrients from the host
Mature proglottid
male and female reproductive organs
budding
Gravid proglottid
breaks off
contains fertilized eggs
Phylum Nematoda
roundworms
pseudocoelomate
filled w/ fluid
hydrostatic pressure
pushes outward
creates hydro skeleton
ungulates to move and to move things through the GI
1 way gastrovascular cavity
mesoderm is muscle
cuticle is a
protective layer
rigid
Ascaris (Phylum Nematoda)
male is hooked
females are straight
will look for the male hook to mate with if they are not hermaphrodites