midterm 2 Flashcards
bony fish
Osteichthyes
sharks and rays
Chondrichthyes
Devonian period
The Age of the Fishes
chordate subphyla on the way to fish
Urochordata (tunicates/ascidians)
chordate subphyla on the way to fish
Cephalochordata
(“amphioxus”)
from middle Cambrian Burgess Shale is strikingly similar to living amphioxus and is
regarded as one of the oldest fossil chordates
Pikaia
jawless fish
Agnatha
clade of chordate animals with a skull of hard bone or cartilage
craniates
Lagerstätten in China
Chengjiang
suggested by flattened shape and heavy external armour
slow, bottom-grubbing fish
Jawed Fish
Gnathostomes
first jawed fish
Acanthodians
heavily armoured fish
Placoderms
Sarcopterygians, type of jawed bony fish that was very important in the Devonian
lobefins
most commonly called tetrapodomorphs, an extinct group
that evolved into tetrapods
rhipidistians
preserved complex of mountains, lowlands with lakes and rivers, and shallow seas produced by collision of North America and Europe in the Devonian
Old Red Sandstone
preadaptation of sarcopterygians; originally evolved as an adaptation to avoid suffocating when they estivated in drying out riverbeds; useful in air breathing during transition to land
lungs
preadaptation of sarcopterygians; originally meant for increased maneuverability in the water; move independently of one another which helped in moving on land - became limbs
lobe fins
molecular phylogeny shows land plants were probably derived from
green algae
terrestrial plant life is dominated by
= bryophytes + vascular plants
embryophytes
polyphyletic group comprising liverworts, hornworts and mosses; have thin-walled, water-conducting cells but lack xylem
bryophytes
show more advanced features, permit growth upwards and maintain their photosynthetic
platform (=leaves) well above the ground
vascular plants
oldest evidence for terrestrial plant life (from Ordovician)
cryptospores
oldest vascular plant from the Middle Silurian
Cooksonia
earliest true vascular plants
Rhyniophytes
second stage in plant evolution (more xylem, attempts at leaves)
Trimerophytes
Devonian small ground cover, shrubs, and small trees
Lycopods
contain secondary xylem
Progymnosperms
oldest known true forest
Gilboa, Catskills NY state
spore-bearing with feathery leaves
Ferns
ranged from low ground-cover to trees 10m high
Horsetails
first gymnosperms
Seed Ferns
plants bearing a naked seed, i.e. not encased in ovaries
gymnosperms
seed fern from Gondwana
Glossopteris
basal tetrapods
Ichthyostega and Acanthostega
show a superb mixture of fish and tetrapod
features
Tiktaalik
earliest tetrapods; primitive amphibians with rough leathery skin
Temnnospondyls
Carboniferous apex predator; amphibian
Watcheeria
reptiles, mammals and birds grouped together; a clade of tetrapod vertebrates
that lay their eggs on land or retain the fertilized egg within the mother
amniotes
development of this permitted true colonization of the land
cleidoic egg
location of earliest true reptiles Hylonomus from Carboniferous
Joggins, Nova Scotia
no fenestrae (earliest reptiles)
anapsid
one fenestra (pecyosaurs , therapsids and mammals)
synapsid
2 fenestrae (most reptiles, all dinosaurs and birds)
diapsid
early forms of what became mammals; used sail for thermoregulation
pelycosaurids
best known were sail-back reptile
Dimetrodon
dominate Late Permian faunas
and ecosystem; replaced pelycosaurids
therapsids
the ability to produce their own heat and control
their body temperature
thermoregulation
ability to modify their temperature at
least partially
partial endotherms
use of sail back on pelycosaurs
enhanced solar heating
greatest extinction in Earth histor
terminal Permian extinction; the great dying
immense decrease in floral biomass caused boundary to be marked by
coal gap
largest
Phanerozoic volcanic deposits on Earth
Siberian traps
life forms immediately following extinction
disaster biota
increasing biomass and diversity after Permian extinction
recovery phase
taxa same as pre-extinction forms
Lazarus taxa
convergent with pre-
extinction taxa
Elvis taxa
new evolutionary innovations appear after Permian extinction
expansion phase
group including thecodonts, crocodiles, pterosaurs, and dinosaurs
archosaurs
animals with a sprawling posture cannot breathe and run at
the same time
Carrier’s Constraint
stem group of the archosaurs that utilized all three postures
thecodonts
top carnivores of freshwater ecosystems of Triassic
parasuchids
top carnivores of the terrestrial realm of Triassic
crocodiles
small saurischian theropods of Triassic
Eoraptor
due to massive volcanism associated with the opening of the North
Atlantic Ocean
end-Triassic extinction
shows that speed increases with increased mass up to 100 kg
scaling taking inertia into account
smaller animals to be
towards the middle of the herd
social structuring
length of stride/leg length
relative stride length
v^2/gl
dimensionless speed
most dinosaurs were travelling at
ambling speeds around 0.5m/sec (2-5 km/hour)
faster speeds are shown in the dinosaur stampede at
Winton, Australia
smaller dinosaurs were racing at (during stampede in Winton)
3-5 m/sec (11-20 km/hour)
argued that dinosaurs were
warm blooded and presented several lines of evidence to back up his claim
Bob Bakker
able to maintain a constant body
temperature
Endotherms (partly equivalent to homeotherms)
receive their body heat entirely from external sources
Ectotherms (partly equivalent to poikilotherms
produce their own body heat, but
are not able to fully overcome the effects of external temperature changes
Partial endotherms
maintain temperature despite reduced metabolic rates simply by virtue of their large size
Inertial homeotherms (= Gigantotherms)
rapid early growth to maximum
size then no growth for the rest of their life
determinate growth
growth continues until death
indeterminate growth
compact bone of most modern endotherms rich in vascular structures
osteons
in nasal passages of modern endotherms that increase
the area over which blood and moist tissues are exposed to air
nasal turbinates
feathered dinosaur
Sinosauropteryx
three tetrapod groups have ever evolved flapping flight
pterosaurs, birds, and bats
(Darwin’s chief advocate) proposed that birds evolved from dinosaurs
Thomas Huxley
-3-fingered hand
-clavicles fused to form proto-wishbone (furcula)
tenanurid dinosaurs
represent the last dinosaurian stage
before birds
Maniraptorid dinosaurs
for flexibility in slashing attacks (permitted
flapping and ultimately flight)
half-moon-shaped wristbone
symmetric and hence were most likely used for maneuverability and
display
plumose feathers
The first bird
Archaeopteryx
location of first bird
Solenhofen Limestone of Germany
conifers, cycads and ginkgos
gymnosperms
ancestral spruce, pine, etc.
conifers
palm-like leaves with a prominant central seed-cone
cycads
“living fossil” that is unchanged since the Paleozoic
ginkgo
animals and land plants aided the pollination and seed dispersal of plants
vector transport
astropods, bivalves,
scleractinian corals, echinoids, bony fish, and marine reptiles
modern fauna
(coiled cephalopods) were the most abundant swimming invertebrates, medium-
level carnivores
ammonites
(cigar-shaped squidlike cephalopods) also extremely common in Mesozoic marine ecosystems
belemnites
large marine reptiles (Diorama #11)
that solved Carriers Constraint in the oceans
sauropterigians
small dolphin-like, agile, fish-eating reptiles. Gave birth to live
young at sea
ichthyosaurs
were up to 12 m long; long-necked with 4 paddle-like fins.
Mainly fish-eaters that gave birth to live young at sea
plesiosaurs
were large sea-going monitor lizards; redators that ate fish, other
reptiles, and ammonites. They also gave birth at sea
mosasaurs
most advanced therapsids
cynodonts
group of early stem-group mammaliformes
morganucodontids
most primitive living mammals
monotremes (protherians)
marsupials and placentals
therian mammals
give birth to immature young that then develop in the mother’s pouch
marsupials (metatherians)
have a longer gestation period and give birth to more fully formed young
placentals (eutherians)
end of Mesozoic extinction event
terminal Cretaceous event
huge volcanic complex almost exactly the same age as
the terminal Cretaceous extinction
Deccan Traps
large extraterrestrial bodies
bolides
reported iridium anomaly in Italy
Walter Alvarez
quartz crystals with defects characteristic of impact
shocked quartz
impact crater has now been identified
Chicxulub on Yucatan Peninsula, Mexico
best exposed evidence of bolide impact
Hell Creek Formation of Montana
sudden appearance of massive amounts of fern spores
fern spike
Eocene life is exemplified by the Fossil Forest on
Axel Heiberg Island and Messel in Germany
coastal terrestrial dweller, ancestor of whale
Pakicetus
large shoreline carnivores that were capable of functioning both on land and in rivers and streams, ancestor of whale
Ambulocetus
fully formed whales (albeit with tiny vestigial hind limbs); obligate swimmers
Basilosaurus
evolved from toothed ancestors (whales)
baleen whales
elongate cells that form pipes for water flow
xylem
elongate cells that transports sugars from photosynthesis to roots and stem
phloem
to bring oxygen to roots and carbon dioxide to leaves
intercellular gas transport tubes
structural material that adds strength to xylem
lignin
first vascular plants best known from where
Rhynie Chert, Scotland
flowering plants, dominant today, tough outer coat around seed
angiosperms
fossil bed of feathered dinosaurs from Cretaceous
Liaoning Province, China
most common Mesozoic mammal
multituberculates
fossil beds with marsupials and placentals found where
Jehol (Liaoning, China)
can help to determine relative age in any single section
superposition
strata are deposited in horizontal layers that are parallel with each other
Law of Original
Horizontality
strata are continuous over lateral distance
Law of Original Continuity
can build up a composite section that shows all
the rock strata in the region in their proper relative ages
correlation (of rock sections)
subdivision of geologic time using divisions based on their fossil content
biostratigraphy
radioactive isotope used in dating
radioisotopes
feature of radioisotopes used to determine age
half life
organic fossils <60,000 years old can be dated directly using
C 14 dating
highly
precise, with analytical errors less than 1 million years on volcanic minerals more than a
billion years old (dating)
U/Pb dating
the major unifying theme in earth science
plate tectonics
first proposed idea of continental drift
Alfred Wegener
geological feature down the center of the Atlantic
mid-ocean ridge
magnetic directions recorded
in rocks to determine the latitude at which the rocks were formed (used to prove plate tectonics theory)
paleomagnetics
oceanic crust is constantly being created at the mid-ocean ridges and consumed in
subduction zones
continental breakup begins as a
Rift Valley
spreading of continental plates produces a
linear sea
oceans are transitory features that are created and destroyed as mega/super continents alternately
form and then disperse
Wilson cycle
represents a second wave of major impacts that
would have sterilized the upper oceans
Late Heavy Bombardment
sun only 75% as bright
faint young sun
Formation of Simple Organic Molecules experiment
Miller-Urey Experiment
model for early life where proteins are the first complex molecules synthesized
proteinworld
model for early life where RNA are the first complex molecules synthesized
RNA-world
experiment shows that self-replicating living systems can consist of
little more than a short strand of RNA
Spiegelman Monster
performed the same experiment (Spiegelman experiment) but without providing a living organism as a seed
Eigen
Spiegelman Monster and Miller-Urey Experiment are examples of
evolution in a test tube
reports of possible fossil life on Mars shown by
Martian Meteorite
Archaea and Bacteria typical of very hot and acidic waters
archea
model spanning all life
universal tree of life
occur in areas having high heat fluxes both on continents, near convergent plate boundaries, and on the ocean floor, near the mid-ocean ridges
hydrothermal systems
less deformed rocks contain Earth’s oldest definite fossils
Pilbara Craton of Western Australia and Barberton in South Africa
filaments and spheres of carbon that reflect the cell walls of unicellular organisms
organic microfossils
where oldest microfossils formed (disproves Darwin’s theory of a warm little pond)
volcanic caldera
extreme environment where modern stromatolites thrive
Shark’s Bay Australia
Proterozoic is known as the age of the
stromatolites
on the north shore of Lake Superior (nearly 2 Ga) is the most important and
famous Early Proterozoic fossil locality
Gunflint Chert
indicate that iron was in a
reduced state in the oceans
banded iron formations
cannot tolerate oxygen
anaerobic
used O2 if available, otherwise use anaerobic pathways
amphiaerobic
fixes carbon dioxide (CO2) and liberates oxygen (O2) as a byproduct of metabolism
photosynthesis
formed in the immediate vicinity of cyanobacterial concentrations during the iron ocean stage
oxygen oases
first stage in oxidation event
iron ocean
second stage in oxidation event
canfield ocean
atmosphere, shallow ocean, and deep ocean all oxygenated
modern ocean
The transition from an oxygen-free world to one with limited oxygen in the atmosphere and shallow seas
great oxidation event
shielded Earth from UV radiation
ozone layer
utilizes oxygen pathways
aerobic
organisms whose cells have a membrane-bound nucleus
eukaryotes
suggested that eukaryotes
represent a endosymbiosis
Lynn Margulis
organic microfossils with large size and complex ridges or spines
architarchs
probably represent multicellular algae
of unknown groups
algal compressions
represent the
oldest complex algae showing cellular structure
red algae
ancestors of land plants
green algae
sister group to the animals
fungi
roots of this record the massive continental collisions that produced Rodinia
Grenville mountains
breakup of Rodinia produced an ice age called
snowball earth
biological events and processes that have driven the course of life on our
planet
evolution
total amount of genetic information coded on all the individuals in the population
gene pool
genetic information of an individual is coded as a series of nucleotides
DNA
change in one or more nucleotides on the DNA
mutation
“survival of the fittest” during the competition for food, living space and mates + avoidance of
predators
natural selection
examples of survival of the fittest
pepper moth and Darwin’s finches
similar life habit in a similar environment leads to the
evolution of similar morphology among organisms that are completely unrelated
convergence
convergent structures
analogous
example of an analogous structure that evolved five times in placental and marsupial mammals, and therapsid reptiles
sabre-tooth
organisms evolve as a response to changes in their environment, but also in response to
evolutionary changes in other organisms
coevolution
evolutionary competition between predator and prey
arms race
a relationship between two species that is beneficial to both
mutualism
theory that species must constantly evolve or
they will go extinct
red queen effect by van valen
biological classification of organisms must reflect evolutionary history
phylogeny
unicellular, lack a cell nucleus or organelles
prokaryotes
distinguished mainly on differences in DNA and proteins
domains
mostly “normal” prokaryotes
bacteria
mostly “extremophile” prokaryotes
archea
includes all single and multi-celled eukaryotes
eukarya
based on hierarchy proposed by Carl von Linné
linnean classification (know classification)
a group of organisms believed to have evolved from a common ancestor
clade
common ancestor and all its descendents
monophyletic group
more than one ancestor which evolved separately from different groups
polyphyletic group
common ancestor but does
not include all descendents
paraphyletic groups
relating to original ancestoral features =pleisiomorphies
basal
first appear in the clade =apomorphies
derived
shows the order of evolutionary appearance of derived characters
cladogram
provides a “ruler” to measure the time of origin of different clades
molecular clock
remains of ancient organisms
fossils
what bones are made of
phosphate
conditions of fossilization
taphonomy
what shells are made of
carbonate
shells leave these in rocks
molds
composed of complex sugar
cellulose
when wood’s pores are filled with silica (produces quartz)
petrified
deposits of fossils with preserved soft tissues are known as
fossil Lagerstatten
the process by which chemicals present in organic matter are decomposed or oxidized into easily available forms to plants
mineralization
fossilized pine tar
amber
most visible fossils represent
preserved hard parts
provide information about fossil behaviour
trace fossils
period of global glaciation at 635 Ma
Marinoan glaciation
the youngest
Proterozoic glacial deposits worldwide
gaskiers glaciation (580 Ma)
the world’s first
large soft-bodied eukaryote
when life got big
oldest Ediacaran fossils known anywhere, found near
Mistaken Point
mistaken point dominated by highly fractal forms called (ediacaran fronds)
rangeomorphs
failed experiment in evolution
extinct clade
how ediacaran organisms fed without mouths
suspension feeding
taking dissolved chemicals out of seawater
osmotrophy
forms with segmentation and bilateral symmetry interpreted as mobile bilaterian that grazed on microbial mats (stem group bilaterians)
Dickinsonia and Kimberella
primitive examples of simple crown-group animals signified what age
dawn of animal life
proposed that all Ediacaran taxa are more similar to each other than they are to any living organisms
Dolf Seilacher
Dolf Seichlacher named this single eukaryotic group as
Vendobionta
ancestral taxa that eventually evolved into more recent organisms
stem group
shown by fronds of extinct clades above sea bottom that are similar to modern communities of suspension feeders
tiering
another term for ediacaran biota
garden of ediacara
wide variety of animals burst onto the evolutionary scene after Ediacaran extinction
Cambrian explosion
profound and rapid diversification event
evolutionary radiation
internal fluid-
filled cavity
coelome
have a coelome
coelomates
collection of species composed of the living representatives of the collection
crown group
a primitive sedentary aquatic invertebrate with a soft porous body
sponges
first skeletal reef-
builders, went extinct at the end of the Early Cambrian
archaeocyathan
shell fossils from Cambrian
small shelly fossils
have a soft unsegmented body and live in aquatic or damp habitats
molluscs
small shelly fossil that had spines that armoured the body
sclerites
type of marine invertebrate with shells that have two valves attached along a hinge
Brachiopods
invertebrate group dominant in Cambrian
Arthropods
extinct marine arthropod with segmented hind part divided into three lobes
trilobite
stem groups arthropods known from Burgess Scale
Marella and Anomalocaris
fossil-bearing deposit of hard and soft bodied Cambrian fossils in British Columbia, Canada
burgess scale
marine invertebrate animals with a five part symmetrical body
echinoderm
consists of animals with a flexible rod supporting their dorsal or back sides from Cambrian
chordates
Cambrian burrows show consistent, complex patterns that are repeated worldwide and
probably reflect behavioural coding on the genome
when life got smart
evolutionary development of increasingly sophisticated armour
and weapons in Cambrian
Cambrian arms race
caused by the Cambrian arms race
agronomic revolution
cycles of assembly of continents
supercontinent cycle
characterized by ice-covered poles, narrow climatic belts, and low sea
levels
icehouse climate
characterized by broad tropical belts, warm temperate conditions to the poles, and high sea levels
greenhouse climate
analysis of this helped to illustrate history of Neogene cooling
oxygen isotope
analyses
divided all Phanerozoic marine animals into three overlapping Evolutionary
Faunas
Sepkoski
Cambrian, paleozoic, modern faunas are called
evolutionary faunas
Cambrian fauna were categorized as
mud grubbers
evolution of these new paleozoic faunas
armoured filter feeds and pelagic predators
established the Paleozoic Evolutionary Fauna
Ordovician radiation
significant and geologically instantaneous drops in diversity
mass extinction
> 50% family extinction;
major extinction
10-50% family extinction
intermediate
3-10% family extinction
lesser extinction
areas with distinct biotas
biogeographic provinces
shallow seas that covered most of North America in the Ordovician
epeiric seas
analogous to terrarium thicket
fringing reef
tidal zones in the Ordovician
supratidal and intertidal flats
a system of interlocking and interdependent food chains
trophic web
easily categorized ways of life that have evolved repeatedly among different taxonomic
group
guilds
largest carnivorous land mammal ever, present in the cenozoic
Mesonychids
small to mid-range ferret-, cat-, dog-, and wolverine-type carnivores
creodonts
an order of mammals with powerful jaws and adapted teeth
carnivora
knock down trees to eat the leaves, prevents trees from growing, preserves savannah ecosystem
megaherbivores
eat different levels of grass in savannahs
grazers
long necks, eat from the tops of trees
browsers
animals that feed on a mixture of foods
mixed feeders
stabbing and bone crushing predators
carnivores
extensive extinctions amongst the archaic mammals in the Eocene-Oligocene boundary
la grande coupure
even-toed ungulates
artiodactyls
odd-toed ungulates
perissodactyls
perrisodactyls that were exceptionally large herbivores
titanotheres and chalicotheres and Indricotherium
miocene was the
age of horses
ancestor of modern horses
Hyracotherium
made up of silica eliminated grazers with short teeth and favoured long-toothed grazers
C4 grasses
long toothed grazers
hypsodont
evolved in Africa and includes all modern elephants
Afrotheria
evolved in South America and includes all modern sloths, armadillos, and South American anteaters
Xenarthra
placental clades from he northern continents of
Europe + Asia + North America
Boreoeutheria
superb record of mammal evolution here
Riversleigh Australia
mammals migrated freely between North and South American continents
the Great American Interchange
early branch off from primate lineage
plesiadapids
lemur-like forms in primate evolution
adapsids
tarsier-like forms in primate evolution
omomyids
Biological order that comprises prosimans, monkeys, apes, among which humans
primates
monkeys + apes, evolved from tarsier like forms
Anthropoids
near the common ancestor of the apes and the Old World monkeys
Aegyptopithecus
classic representative of the Homonoidea
Proconsul
Chimpanzees
pan
all primates more similar to Homo than to chimpanzees
hominins
caused by Arabia drifting away from Africa
East African Rift
the first find of australopithecines
Taung child
where the first find of australopithecines was found
Raymond dart
oldest generally accepted hominin
Sahelanthropus
relatively complete female skeleton; oldest partial hominin skeleton known anywhere
ardi
faculative biped who was equally adept on
the ground or in the trees
Ardipithecus
can walk but doesn’t do it all the time
facultative biped
active grasping and climbing for primates
palmigrade climbing
using knuckles as walking support
knuckle walking
climbing by propelling body from tree to tree
tree swinging
nearly complete skeleton of gracile australopithicines
Lucy
australopithicines subdivision groups
gracile and robust
robust australopithicines commonly placed in what genus
Paranthropus
where walking or running on two legs is the primary method of locomotion
obligate biped
trackway showing bipedal locomotion
Laetoli
first possible controversial tool appearance
Lomekwian
oldest reasonably complete skeletons - of a facultative biped who was equally adept on the ground and in trees
Ardipithecus
obligate biped that lived mainly on the ground and had
a mainly vegetarian diet including considerable roughage
Australopithecus
hammerstones and simple flakes tools used by homo
Oldowan
hand axes show deliberate manufacture, represent the world’s first permanent tools
Acheulean
states that different populations of H. erectus in Africa, Europe,
central Asia and SE Asia maintained some genetic interchange, and eventually evolved into
the different races of H. sapiens
multiregional theory
states that H. sapiens evolved in Africa. All hominid populations living outside Africa were evolutionary dead ends that went
extinct about the time that H. sapiens spread out of Africa
monogenesis “out of Africa theory”
more sophisticated tools used by Neanderthals
Mousterian
bone dictating capacity of speech
hyoid
represent a parallel clade of extinct humans, but are known almost entirely from
molecular data
Denisovans
complex tool used by Homo sapiens
Aurignacian
life is affected by major physical perturbations which cause accelerated evolutionary response
court jester effect (by Barnowsky)
species living on the edges of the Namib Desert that does not knock down trees
the desert elephant
top cambrian predator of the seas
Anomalocaris
top paleozoic predator
cephalopod
top predator of the devonian
placoderms
first amniote to return to water
mesosaurus
top predators of the Permian
shelled cephalopds and sharks
