Ess 104 Mditerm
Variation (3)
- hinders identification of species because not all individuals in a species look the same -ontogenetic (age) juveniles differ from adults; particularly marked in animals that grow by molting; seasonal breeding; colonial growth -population: members of a species not evenly distributed; sexual dimorphism -taphonomic: organism change shape and complexity by deformation, dissolution during fossilization; often results in new species
*Abundance of Stromatolites (Proterozoic)
- layers of mound-shaped structures - trace fossils of microbial activity -trapped sediment by cyanobacteria -common in all shallow water settings; declined rapidly due to seaweed
Binomial nomenclature
-2 part naming system; genus and species -based on the concept that there are discrete groups of organisms that are morphologically distinct -each group called a species -same names as biologists
*Appearance of complex cells: Protists (Sexual reproduction and Multicellular organisms)
-2-1 billion years ago - Protists: single-celled eukaryotes; enslaved bacteria; 1.85 billion years ago -eukaryote: organisms with complex cell structures - seaweed: responsible for the decline of stromatolites -sexual reproduction: jumpstarted evolution; red alga was the first known sexually reproducing organism
*Great Oxidation Event
-2.4 billion to 2.2 billion years ago -until then only oxygen in small amounts - oxygen was grabbed and used by iron, sodium, and cH4 -Banded iron formations turn into red beds after oxygen sinks disappeared
Oldest body fossil evidence of life
-2.6 billion years ago -South Africa -clear evidence of cellularity, complex behavior, interaction with surrounding environment -dividing cells and matting filaments in stromatolites
Age of Cyanobacteria (Photosynthesis)
-3.4 billion years ago -endosymbiotic; photosynthesizing bacteria; abundant microfossils in Chert -little morphologically change over time -*responsible for oxygen in the atmosphere by photosynthesis
Oldest visible evidence of life
-3.47 billion years ago -trace fossils in Australia -stromatolites with dome structures; kerogen-rich
Chemical fossils oldest evidence of life
-3.52 billion years ago -Kerogen limestone in Australia
*Plate Tectonics
-3000 million years ago -7 plates; movement of Earth's lithosphere -ride on fluid aesthenosphere so they collide and split apart -Rodinia was first supercontinent
*Oldest known rock
-4.28 billion years ago -From stable craton -Northern Canada
*First life
-4000-3500 million years ago -biomarkers, chemical fossils, and isotopic fractionations
*Snowball Earth Events
-830-650 million years ago -sun was on 80-90% as bright as it is now -3 events -needed greenhouse gases to stop ocean from freezing over; greenhouse gases started glaciation; shut down photosynthesis and restarted it - organisms adapted to life in hydrothermal vents, extremely cold conditions, and carbon isotopes
Lagerstatten
-a place of exceptional preservation, often soft tissue preservation (Germany) (Burgess Shale/ Canadian Rocks: soft bodied animal preservation that shows early animals had much more diverse body plans than now; Halluucinigina and Wiwaxia)
nature of morphological features (6)
-adaptive -very few neutral features (non-adaptive) -there are limited number of ways an organism can adapt to its environment -most options are already in use -can be extrapolated from a living equivalent -adaptation is not random
3 Problems with the fossil record
-age bias: older the time, the less chance of any rock being preserved -physical destruction: some are more prone to damage -rarefraction: smaller the sample the less chance of finding every type of fossil
Before Lamarck (Erasmus Darwin)
-believed all life depended from a common ancestor -thought transmutation was due to competition and sexual selection -had no proof 1721-1802 -charles darwin grandfather
Carl Linnaeus
-binomial nomenclature/taxonomy -grouping of genera into higher taxa that were based on characteristics of shared similarity -DUMB KING PHILLIP CRIED OVER FAILING GRADE SIX
*Plate Tectonics Influence
-climate -ocean circulation -geographic isolation -geographic proximity -geology and biology are linked
How to become a fossil (5)
-die -rapid burial -preservation -sediment or soil has to become rock through mineralization/lithification -survive through time
Evolution by natural selection (3)
-driven by competition for food, space, and sexual partners
Fossils
-evidence of past life in rocks -Latin: (fossus); something that was dug up
O.C. Marsh
-evolutionary series -horses evolution (^ size, brain, teeth, and smaller toes) -declared by T.H. Huxley to be conclusive proof
Phylogeny
-family tree -fundamental taxonomic grouping based on a shared basic body plan or pattern of structural organization -each branch called a clade -evolutionary lineage; all derived from a common ancestor
*Moon
-formed 4.5 billion years ago (object the size of Mars collides with Earth in a Glancing blow; collided and formed the Moon because it couldn't resist Earth's orbit)
*Earth
-formed 4.6 billion years ago
Names (Nomenclature)
-generic (groups of similar organisms) AND species (individual species) -ether italicized or underlined -Latin name always capitalized
2 types of speciation
-gradual (phyletic gradualism); Darwin -abrupt (punctuated equilibrium); Eldredge and Gould
Chemical fossils
-isotopic fractionations: isotopic evidence trapped in minerals; survives thermal and mechanical trauma well; diagnostic -biomarkers: found in oil and kerogen; easily contaminated
pterosaur flight (features analogous with other flying organisms) (3)
-large pectoral muscle scars -fur or downy feathers, so high body temperature -wings homologous with bats
Fossils are rare
-less than 1% of all organisms become fossils -hard parts: bone teeth, shell, wood -soft parts: extremely rare
what can we learn from functional morphology (3)
-lifestyle: did it fly? -habits: what did it eat? -behavior: did it burrow, climb, run?
2 levels of evolutionary process
-microevolution: origin of a species over relatively short biological time -macroevolution: above the species level; over long geological time intervals
*Archean Fossils
-microfossils -chemical fossils -stromatolites
relative geological timescale
-mid 1800s in Europe -units o relative time based off rocks -each major time units identified and characterized by the fossils in the rocks and almost all are marine (sea) fossils -given local names -global naming system and international standard
Sedimentary rocks
-most (90%) are results of sediment and are deposited by water -most often found in oceans, rivers, lakes, and swamps -occasionally found in sand dunes or volcanic ash
*Great Oxidation Event
-most living organisms didn't use oxygen because it was poison to them -called extremophiles -consist of organisms that live in and around places such as hydrothermal vents, geothermal pools, and methane sweeps
Evolution by natural selection a nutshell (4)
-mutation and recombination introduce heritable traits -natural selection acts on the phenotype -end result is a species change over time -with enough change becomes a new species
Taxonomy
-naming species -the STUDY OF GROUPS (taxa) -hierarchal system of group -Carl Linnaeus 18th century -all names are latin
Phyletic gradualism (4)
-occurs in a stable environment -large number of small steps -sudden change is only apparent because of gaps in fossil record -transitional forms exist but are usually not preserved (ocean floor)
Punctuate equilibrium (4)
-occurs in unstable environment -most of the time no evolution -small number of large steps, occurs rapidly -foossil record is accurate becuase environment changed rapidly and transitional forms are rarely preserved (land, shallow ocean, lakes)
evolutionary series
-set of fossils showing taxa changing from one morphology to another over time -(whales, horses, dinosaurs)
Microfossils
-small and simple -hard to recognize -not diagnostic of biological relationships
Species can have 2 evolutionary fates
-speciation (give rise to a new species) or -extinction (all individuals can die) longevity depends on environment and type of organisms
non adaptive influences (5)
-structure: some organisms are stuck with it -heritage: some born with handicap -trade-off: some genes coded with benefits and deficits (humans) -compromise: some features used for more than one purpose (feathers for flight and warm) -limits to genetic diversity: organism may not have necessary genes (cheetahs cannot run any faster; fish can't live outside of the artic)
Paleontology
-study of fossils -don't study human remains
stratigraphy
-study of rocks sequence time -concerned with the order, relative position, and age -volcanic flow and ash layer also form strata
Before Darwin (Jean Baptiste Lamarck)
-termed "transmutation": passing on of an acquired trait (giraffe neck) -believed mechanism was inheritance of acquired traits -recognized change over time -1744-1829
functional morphology
-the study of the structural adaptations an organism makes to its environment and lifestyle -form follows function
3 approaches to functional morphology
-theoretical morphology -biomechanics -paleontological morphology
early earth
-time Earth was born to time of life -4.5 billion years ago to 540 million -90% of Earth's lifetime -Concerned with the Precambrian Era; Proterozoic (3) and Archean Periods (2) - Oldest Period is Hadean (1)
Sediment
-tiny particles of weathered and eroded rock -eroded in uplands, deposited in lowlands -each layer called a strata; stratum
why do we think form follows function (3)
-tradition: nature is parsimonious; doesn't expand unnecessary energy unless needed -natural selection: drives organism toward optimum morphology for their environment -observation: we see cases where organisms with different phylogenetic origins converge with the same morphology
*Oldest known thing
-zircon from Australia -tiny speck of mineral in a sedimentary rock -4.4 billion years old
Four fundamental reptile groups
1. Basal or stem reptiles 2. Anapsida: only fossil reptiles, 0 fenestra 3. Diapsida: almost all other living and extinct reptiles, including dinosaurs, 2 fenestra 4. Synapsida: the group that gave rise to the mammals, 1 fenestra
Problems with Biological Species Concept (4)
1. can't breed fossils 2. fossils often only represent part of an organisms (ex. plants) 3. where do we place boundaries between species in time if things are gradually changing 4. most difficult: breaks in fossil record, in some cases don't have enough material which causes apparent breaks in a continuously evolving lineage
Paleontological Species Concept (3)
1.modified biological species concept: spiced is a group of organisms with a degree of morphological variation similar to modern biological species 2. evolutionary species concept: evolutionary lineage evolving separately from other lineage 3. form species concept: fossils of similar morphology are treated as a species even if they resent several biological species
Iguanodontids
120-130 mya Europe more primitive Ornithopoda spike on digit 1 of the hand beak on tip of jaws also Camptosuars, Late Jurassic
Plesiosaurs [mesozoic]
15 m long carnivores triassic-cretaceous apparently bore live young; crawled out onto land to mate probably warm blooded Elasmosaursus;Tanystropheus
Richard Owen
1842 described all the giant lizard material known in England at the time using the name Dinosauria which "meant fearfully great lizards"
Paleozoic reef building (3 cycles)
1st: Lower Cambrian reefs were dominated by ARCHEOCYNATHIDS with stromatolites and other photosynthetic algae 2nd: Late Cambrian to Late Devonian; reeds were dominated by CORAL SPONGE BRYZOA ASSEMBLAGES in association with cyanobacteria; very high diversity 3rd: Carboniferous to the end Permian; dominated by CORAL; dense CRINOID REEFS
Cambrian radiation (3)
1st: small shelly fossils ancestral mollusks, brachiopods; other look like armor for worms ranged from late ediacaran to early Cambrian
glossopteris
290-248 mya no living relatives dominant Gondwanan lineage Pangea may have been a preciser to angiosperm
leaves
40-50 million years after the first vascular plants colonized the land may have evolved in plants similar to mosses
vascular plants developed by
400 million years ago, early Devonian
After Basilosaurus: Remingtonocetus, Indocetus, Protocetus, Rodhocetus
45 mya in Pakistan 44-45 mya elongated skull teeth much more like regular mammal teeth with differentiated molars nostril near front of snout
Homonid Evolution
6-4 mya: first homonids (Miocene): flat face, small canines, upright posture, small brain, big brow ridges, sagittal crest, not clearly bipedal restricted to Africa until 2 million years 4-2 mya Australopithecus: many species, clay bipedal, brain relatively small for body size Not on human lineage Paranthropus: several species, heavy jaw, large teeth, sagittal crest 2 mya Genus Homo; H. habilis' large brain, made stone tools, omnivorous, short 1.5 mya H. erectus: modern height, brain size 75% of modern, no chin, large brow ridges, used dire and tools; migrated out of Africa to Eurasia, survived in Asia until 200k years ago Homo saoiens arose 200k iin Africa, H. neanderthalensis lived in Eurasia at same time but went extinct 40k years ago
ediacaran fossils/time (5)
600-545 million years old, named after 1st site Ediacara in South Australia impressions in sandstone, worldwide described in all continents except Antartica marine many look like jelly fish, sea pens, flatworms, but other unlike any living or fossil animals some say animals other say weird beasts not related to animals
End Cretaceous Mass Extinction
75% of species died including: dinosaurs, marine and flying reptiles, ammonites, belemnites a but high altitude flowering plants and benthic foraminifera hardly affected cause by giant meteorite impact in Mexico Alvarez' evidence includes shocked quartz, iridium-rich layer, soot, tektites
Pleistocene megafauna
American mastodon giant polar bear woolly mammoth giant ground sloth
Devonian: Vertebrates invade land
Amphibian ancestors: lobe finned fish breathed with lungs, lobe fins became the limbs of the tetrapods, four legged animal
Two groups of Ankylosaurs
Ankylosaurs: bony club on the end of tail, heads covered by extra bony plates Nodosaur: no club on tail
Neogene Terrestrial Faunas
Anthropoid primates radiate giant mammals (mammoths, ground sloths, elk) evolve during ice ages, extinct as humans appear: hunting overkill, climate change, vegetation change from human fires, meterorite impact
Important sauropods
Apatosaurus formerly Brontosuarus Brachiosaurus: only sauropod that has longer front legs than hind legs and that could lift its head up high Argentinosaurus, largest dinosaur
largest dinosaur
Argentinosaurus up to 38 m long 15m high at shoulder 80-100 metric tons
ornithischians dinosaur classification
Armored dinosaurs Marginocephalia Ornithopoda
Types of fossils
Body: (appearance) bone, leaves, shells Trace: (behaviors) burrows, poop, eggs, footprints but sometimes don't know what species made them
Mid Eocene
By mid Eocene all groups of mammals had evolved including bats and whales
*Photosynthesis
CO2+H20—> CH20 (organic matter)+O2
Inarticulate brachiopods
Cambrian fauna bivalved organisms, no teeth, just musculature
rise of animals
Darwin thought animals evolved at the start of Cambrian when first fossils skeletons appeared now know that animals go back into Proterozoic but debate over how far back
Utah raptor
Early Cretaceous
Oldest of the clades of modern birds
Early Cretaceous 110 million years ago water bird Gensus yumenesis in lake deposits Change Basin Gansu Province, China
Dromaeosaurids
Early to Late Cretaceous, North America, South America, and Asia TRUE RAPTORS
Gideon Mantell
England, 1825 described very large teeth his wife Maryann has collected along with a few bone scraps named it Iguanodon: teeth like iguana lizard bigger than any iguanas giant lizard
Eoraptor and Eodromaeus
Eoraptor believed to be ancestor of giant sauropod Eodromaeus believed to be the ancestor of theropods
oldest known dinosaurs
Eoraptor; 230 mya; dawn plunderers; ancestor of giant sauropods Eodromaeus; 232 mya; dawn runner; ancestor of theropods Both found in the same formation in Patagonia 1 meter, bipedal and slender build, weigh 8 kg, carnivorous teeth
Paleogene predators
Hoplophoneus and Dinictis false saber tooths 1.1m long claws only partly retractable`
Horse evolution in the Eocene
Hyracotherium: tiny horses (small dog), 4 toes, specimen from Messel, Germany
Rocks (3)
Igneous: forms from molten rock above or below the surface Sedimentary: from above the surface, combination of three rocks, only rock that contains fossils Metamorphic: forms under the surface due to heat and pressure
Basilosaurus
Late Eocene 36-40 mya Egypt and US Gulf Coast 18m long with hind limbs that were very small and probably lay within the body muscles Zygorhiza was more like a dolphin, 5m long
Rhynia
Lower Devonian vascular plant 412 million years ago named for type locality: Rhynie,Scotland primitive vascular system grew to 18 cm
What is the ancestral group of these quadrupedal probably semi aquatic pre whale mammals?
Mesonychids carnivorous relatively large head with biggish brain small flexible backbone teeth similar to those of early whales small dog sized lived around Eocene Paleocene boundary time
when era did dinosaurs live in?
Mesozoic Era Went extinct after the Cretaceous-Paleogene mass extinction 65 mya
smallest dinosaur
Microraptor from China 2003 Scipionyx from Naples, Italy 1998 40 cm from the nose to the tip of tale
Ocean Circulation
Middle Eocene ocean circulation: continent configuration did not allow widespread circulation of polar water masses Eocene Oligocene boundary: Cold dense water dropped to the ocean floor, and moved north up each ocean basin. This stimulated much faster circulation rates and the whole planet cooled down
Carboniferous
Mississippian- Pennsylvanian massive coal deposition in the Northern hemisphere in swamps with club moss, horsetails, tree fern, forests 30 meters high giant insects because so much carbon terrestrial vertebrate faunas dominated by AMPHIBIANS (labyrinthodonts) with first reptiles evolving, lobe finned fish
Allosaurus
NOT a tyrannosaurid more primitive 3 fingers on hand
Radiation of grasslands
Oligocene-Miocene, with most rapid radiation in Miocene in response to lower CO2 levels the atmosphere causing a cooler, drier climate
two dinosaur clades based on pelvic structure
Ornithischia: bird hipped, all herbivores Saurischia: lizard-hipped
Mark Goodwin @ U.C. Berkley
Pachycephalosaurus skull domes were for species recognition or sexual selection
Paleogene terrestrial scene
Paleocene forest Eocene coastal plain
Early Cenozoic animals
Phenacodus: sheep sized herbivore with improved capabilities for running Endelodont: pig relative; 2m high at the shoulder
Paleogene Mammals
Placental mammals became dominant tetrapods, except in Australia, South America: marsupials Early Paleogene: Dominated by orders now extinct (archaic order) Most modern orders arise
Ambulocetus natans
Punjab Province, Pakistan Early Eocene- 50 mya 4 walking limbs long tail and skull
Permian Terrestrial Life
REPTILES DIVERSIFY dominated by pelycosaurs(Dimetrodon) in early permian mammal like reptiles (therapsids) in late permian
Rodhocetus
Rodhocetus and Indocetus 2-4 m long well developed hind limbs (only femur and tibia bones found to date) unlike land mammals, no fused vertebrae in the pelvis (called a sacrum)
theropods characteristics
Saurischian hip structure bipedal hollow limb bones sharp seated teeth furcula: clavicles fused into wishbone foot like a birds: 3 digits pointing forward, one pointing backward
first true land plants
Silurian cooksonia 428 million years ago found in England no branches but sporangia at terminus lived in swampy areas 6.5 cm tall no vascular system
The Cenozoic Era
The Age of Mammals 2 periods: Paleogene & Neogene subdivide into 7 epochs: Paleoeocene, Eocene, Oligocene, Miocene & Pliocene, Pleistocene, Holocene
oldest dinosaur
Triassic 230 mya
Armored dinosaurs
Two groups: Stegosaurus (Late Jurassic) and Ankylosaurids (Cretaceous) ornithischians with 1. bony armor 2. quadrupedal stance 3. small heads and the smallest brains/body weight Stegosaurus plates probably for display Ankylosaurids: no plates along spine
plant
a multicellular eukaryote capable of carrying out photosynthesis in its cells which contain chloroplasts and have cellulose in their cell wall
seeds
about the same time as leaves early Devonian- new reproductive system not as fragile more easily and widely dispersed
Natural selection occurs in both
abrupt (punctuated equilibrium) and gradual (phyletic gradualism)
Odontocetes
active hunters- eat fish, squid, smaller marine mammals large brain all species have teeth sing nasal opening (blowhole) but almost no sense of smell echolocation strong forelimbs and only the remnants of the hip bone
True fossil record through time
after accounting for the three problems/ factors we get
Marginocephalians
all are characterized by a bony shelf extending over the occipital region of the skull Pachycephalalosaurus: thick-headed reptile, End Cretaceous in North Amemrica, bipedal
Pleistocene Megafauna
all mammals camels giant sloth (megatherium) cave bears irish elk dire wolf saber toothed cat (smilodon) mammoths mastodons all extinct at the end of Pleistocene
Cenozoic Marine Life
ammonites and most lobed finned fishes extinct scleractinian corals were main reef builders bivalve mollusks replaced brachiopods, brachiopods now minor and mostly deep sea echinoids, crustaceans continued radiation snails became carnivores and had a huge radiation plankton: largely wipes out at K-Pg boundary; foraminifera, coccoliths, diatoms, dinoflagellates now radiated ray finned fish and sharks took over sea WHALES evolved in Eocene Cephalopods represented by octopus and squid. Nautilus is only shelled cephalopod remaining
limiting factors
an environmental factor that controls the growth, abundance, or distribution of a population of organism
Cretaceous plants
angiosperms (flowering plants) appear and dominate insects radiated and along with angiosperms helped pollinate
cretaceous
angiosperms (flowers)
Mesoproterozoic (3) A.S. B.R.
animal trace fossils adolf seilfacher found worm like trails in Indian rocks (1.6) billion years ago Birger Rasmussen found worm like tracks in Australian rocks 1.2-1.8 billion years ago along with molds looking like jelly fish
Giant Eurypterid (sea scorpions) [paleozoic]
anthropoids closely related to modern scorpions ordovician - permian black or fresh water may have spent short periods on land
gingko
appeared in permian 270 million years ago closest living relative to cycad
true gymnosperms, conifer
arose in later permian probably from ferns naked seeds no flowers or fruit air born pollen very efficient vascular system
Giant Carboniferous millipedes and giant flying insects [paleozoic]
arthropleura may have been herbivorous based on fern spores in gut and coprolites insects: meganeura, fed on other insects and amphibians due to excess oxygen in the atmosphere
trilobites (3)
arthropods charactertistic longitudinal and transverse tripartition gave their name base of the Cambrian was first described by the first appearance of trilobites but now by worm traces
mysticete whales
baleen whales range from 6m-34m long 3-200 tons 2 blowholes no echolocation thick layer of blubber (fat) under skin jaws modified to house huge baleen plates, attached to the upper jaws relatively smaller brain
Classification of reptiles
based on skull characteristics, especially # of fenestra fenestra: window or hole eye socket: orbit post orbital fenestra: concerned with number of fenestra behind the eye socket
Cenozoic [water]
basilosaurus not lizards, but whales Eocene 45-34 mya no blow hole so had to stick nose out of water to breathe vestigial legs and toes ate fish, sharks, squid
most common biominerals (3) California cars California people sun
calcium carbonate- calcite and aragonite (shells of mollisols, foraminifera) calcium phospate- apatite (vertebrate bones and teeth) silica (radiolarians and dinoflagellates)
Helicoprion [paleozoic]
carboniferous- early triassic shark like fish- cartilage rather than bone mostly known from the fossilized whorl actual location of whorl unknown
Jurassic Terrestrial Life
carnivorous dinosaurs: theropods birds descended from small feathered theropods first bird Archeapteryx, identical to the theropod Comoposgnathus
prior to uniformitarianism
catastrophism: the idea that the Earth is primarily shaped by sudden cataclysmic events that don't necessarily operate now
biologically controlled biomineralization
cellular activities direct mineralization including type of mineral , morphology, and final location
Devonian: First Forests
club mosses started getting trunks: "trees" by late Devonian forestry of tree ferns, horsetails, club mosses, GYMNOSPERMS deep roots stabilized soil and slowed erosion but also speeded weathering, deepened soils
Also in the Cambrian
conodonts: teeth of lamprey like chordate
Pleistocene glaciations
continued cooling of climate permanent ice at both poles series of glacial/interglacial episodes
permian
cycads, gingkoes, glossopteris
height restrictions
developed cambium layer allowing them to grow into giants
why did leaves take so long?
devoted stomata: tiny pores on surface of leaves for exchange of gases
difficulties of paleoecology (3)
differential preservation skews and loses data a) soft parts are rarely fossilized b) resistant parts may be over-represented fossil beds are composites- they are time- averaged and may include organisms carried in from elsewhere rarity of fossilization
dinosaurs defined
dinos are Mesozoic land living reptiles that walked with upright stance some walked on 4, some walked on hind limbs only (bipedal) walked with legs under body (upright stance) reptiles had splayed stance
divergent evolution
dissimilar organisms that have similar origin and underlying anatomy
carboniferous forests
dominant taxa: lycopods, sphenopsids (horsetails), ferns, progynosperms
Cretaceous Terrestrial Vertebrates
dominated by dinosaur mostly herbivores carnivorous theropods have range of sizes
sauropod salad bar (Jurassic) Giant letter have certain fonts
dominated by gymnosperms, lycopods, horsetails, cycads, ferns
Therapods
dromaeosaurs (raptors)
Hadrosaurids
duck-billed dinosaurs middle-late cretaceous moved in gigantic herds apparently migrating with the seasons most commonly found dinosaur dental battery, crested and non-crested, hooves on toes
Mammalian clade
each group has distinct teeth - we can tell marsupials, monotremes, and placental mammals apart based on their teeth
mammal radiation
early mesozoic mammals were monotremes and marsupials placentals arose in cretaceous most mesozoic mammals were very small ex, Hadrocodium early Jurassic was the size of a paperclip
Velociraptor
end Cretaceous, Monogolia feathers but no flight
Depositional environment
environment where sediment is deposited
whales are artiodactyls
even toed ungulates (hoofed animals) pigs, cows, deer, antelope, whales, sheep, hippos, etc
fundamental principals of paleoecology (4)
every organism is adapted to a certain environment every organism is adapted to a certain mode of life every organism is restricted in its distribution by the limitations of the environment to which it is adapted every organism is directly or indirectly dependent on most or all of the other members of the same community
What is our evidence that these two whale forums are related and that they have a common ancestor in the geologic past?
evidence from living animals, especially homologous structures evidence from fossils
Speciation (evolution)
evolution occurs by natural selection Charles Darwin and Russell Wallace
In conjunction with grasses
evolution of long legged grazing animals: antelope, sheep, camel, deer trend to elongated limbs and high crowned teeth
Diapsid reptiles
extremely successful group of animals including dinos, pterosaurs, lizards, snakes, crocodiles, and all crocodile-like animals from Mesozoic
mammal radiation in Cenozoic
facilitated by empty ecological niches vacated in end Cretaceous extinction new organisms evolve similar adaptions to previous occupants, analogous adaptations
grass
first appeared in mesozoic butt became dominant in Miocene
silurian
first land plants
pro gymnosperms
first seed plants precursors of todays gymnosperms
flowers (angiosperms)
first signals to appear in early Cretaceous, although indirect evidence indicates they could have evolved in triassic rapid radiation in late cretaceous dominate landscape from there on more advanced reproductive strategy with enclosed seeds and a better system for attracting pollinators form and scent
first simple marine plants
first significant fossil believed to be Grypania 2.1 billion years ago
animal colonization (sam can't inhale many sam inhales right)
first terrestrial animals: spiders, centipedes, insects mites, spiders, insects found in the Rhynie chert along with Rhynia
devonian
first vascular plants
Ancient River Deposits
flood rivers = good place to find fossils because 1. great deal of energy 2. river spread out to cover a large area
limiting factors in ALL habitats (8)
food, water, cover, space, predators, depth or altitude, temperature
Nyasasaurus parringtoni
found in Tanzania in 1930s, kept in storeroom, reexamined in 2012 by sterling Nesbitt at UW
skeletal difference between dinosaurs and other archosaurs
fused sacral vertebrae expanded ilium forward facing shoulder girdle acetabulum femur with angled ball joint
earliest triassic dinosaurs
generally small bipedal, long limbs fairly long necks small head with lots of teeth rare found around the world and look similar carnivores
Mesozoic Environment
geography marked by break up of Pangaea, opening of Atlantic Ocean Climate in Jurassic and Cretaceous notably warm due to high CO2 that causes enhanced greenhouse effect, may have been due to eruption of Siberian traps
Sarcosuchus [mesozoic air/land]
giant crocodile 8.75 tons late cretaceous 11-12 m long
Eocene birds
giant predatory bird from Brazil remained one of the top predators into the Miocene all other giant bird lines became more like ostrich like and herbivore-omnivore
Paleozoic monsters
giant trilobites: Isotelus rex Manitoba, Canada Ordovician several more species were found in lagerstatten in Portugal
lycopods
giants 370 million years ago
precambrian/cambrian boundary (2)
golden spike placed at Fortune Head section near fortune, Southeast Newfoundland base of the Cambrian is defined as the first occurrence of a burrowing worm, trichophycus pedum near Fortune on western Newfoundland,Canada
miocene
grass
Carboniferous Permian
great Gondwanaland glaciation GLOSSOPTERIS
horsetail
grew 30 m tall in devonian
cycads
gymnosperms appeared in permian 280 mya grew to 15 m resembles palm tree
Pakicetus
had been found before but not identified or named turned out to be a suitable ancestor to Ambulocetus 52 mya elongated jaw and snout but nostrils near the tip oxygen isotope studies indicate these animals lived in fresh water no echolocation functional legs and long tail
Paleogene Climate
hot early then steady cooling 50 mya Paleocene-Eocene Thermal Maximum: 56 mya thermal pulse due to methane hydrate melting (methane ice) Antarctic ice cap formed Eocene Oligocene boundary: sharp temperature fall 33 million years ago temperature data points are from the shells of benthic foraminifera microscopic marine plants
mammals vs. reptiles
increase in brain capacity so doming of the skull selection for differentiated teeth: incisors, canines, different types of molars therefore selection for single robust jaw bone other bones in Jae become greatly reduced and then became the inner ear bones
Silurian Terrestrial Life (6)
invasion of the land (mosses in ordovician) leafless psilophytes (cooksonia), one species still alive (Psilotum) then spore bearing club mosses (lycopodia) animals terrestrialized along with pants millipede apparently first (tracks and burrows) eurypterids (dominant marine predators) were amphibious (tracks on beaches, dune) marine: rise of armored marine predators, jawed fish
Nyasasaurus Parringtoni
is it a dinosaur? Bone structure and muscle attachments made it likely would be the oldest ever found 240 million years ago if it isn't very closely relation and thus a dinosauriform, evolved mid Triassic
Entelodonts [cenozoic mammal]
killer/hell pigs eocene-miocene probably closer to whales than pigs or hippos omnivores but top predators of miocene
Triassic Vertebrates
land animals dominated by ARCHOSAUR REPTILES replaced therapsids (mammal like reptiles) as main carnivores and later as herbivores (crocodiles are modern example)
Triassic Plants
land plants mostly gymnosperms, cycads, and ginkgos become common
Jurassic Plants
land plants similar: ginkgo, cycads large conifer trees: araucaria, sequoia
Ornithopod characteristics
large herbivores with forelimbs up to 75% of the length of hind limbs facultative quadrupeds: bipedal but could walk on 4 feet if needed or if they were huge
Ceratopsians
last major dinosaur clade to evolve extremely successful high diversity and species in the late Cretaceous in North America Triceratops: 67-65 mya and 9m long; two species Horridus and Prosus; horns and frills used for species recognition and visual communication Torosaurus: 70-65 mya, 7m
Xiphactinus [cenozoic water]
late cretaceous 6m long swam up to 60 km/h ate other large fish and seabirds
Paraceratherium
late oligocene of Eurasia largest land mammal ever: head 8m, skull 1.5 m, 20 tons herbivore related to rhinoceros browser may have had trouble with overheating; warm blooded animals have to dissipate heat fossil record very fragmentary
Megalodon [cenozoic water]
length up to 16m; twice as long as great white teeth 21 cm, jaws over 2 m wide carnivore favorite food: whale miocene-pliocene
PT Mass extinction recovery
long recovery period impoverished faunas, diversity low for 10 million years no coal forests or reefs for 10 million years stromatolites reappear many groups survive with only one genus or species preextinction diversity not achieved until the Cretaceous about 100 million years later
carboniferous
lycopods, horsetails, fern, progymnosperm
What does fossil preservation mean?
maintaining the overall structure of an organism and replacing tissue with another mineral
Eocene Oligocene boundary
major extinction at Eocene Oligocene boundary affected both terrestrial and marine life archaic mammal orders die off modern mammal orders take over isotopic evidence (again from foraminifera shell) of sharp temperature drop; Antarctic ice caps form
Triassic mammals
mammals evolved from cynodont reptiles first mammals appear in late triassic
Jurassic Mammals
mammals small and scare, most groups now extinct included screwed like carnivores Hadrocodium and insectivores Pseudotribos
Cretaceous Mammals
mammals still small but fairly common monotremes (egg laying) marsupials (pouched) appear Placentals (live birth). appear, likely during end cretaceous
Permian Life
marine life like carboniferous on land glossopteris tundra coal swamp flora in Gondwanaland
Ornithopoda
means bird shaped foot included Iguanodontids, Hadrosaurids (duck billed), Lambeosaurids (crested dinosaur), Muttaburrasaurs
archean fossils (3)
microfossils stromatolites chemical fossils
Deinoychus
mid cretaceous
Triassic Marine Faunas (MODERN FAUNA)
modern evolutionary fauna bivalve and gastropod mollusks ray finned fishes, echinoids (sea urchins) ammonites (cephalopod mollusks) important for biostratigraphy
Bird characteristics
modifications to wrist, forelimb, hand enlarged scapula and furcula large, deep keeled sternum fused vertebrae and vertebrae fused to pelvis pygostyle reduced, fused tail pelvis similar but not identical ornithiscian fused leg and foot bones
Mesozoic monsters
mosasaurs: related to snakes and lizards, hinged jaw like snakes top marine predators huge carnivorous- fish, sea urchins, turtles remains found in stomach indicated meals of ammonites, sharks, other mosasaurs
definition of animals
multicellular heterotrophs that in some part of life cycle are mobile
During what time period was there an extinction of reefs?
near end of Devonian
when did echolocation evolve?
new research shows that the origin of echolocation is very early in the evolutionary lineage before whales were fully aquatic somewhere around 45 mya
Feathers
no longer a characteristic that can define birds bc quill knobs on velociraptor
problem with ediacaran fossils
no sign of movement
Lakes and Swamps
no water current so they re great places for fossil preservation
Late Devonian Mass Extinction
occurred in several pulses over 10 million years several orders and classes extinct but no phyla causes unknown but some evidence of meteorite impact but can't explain pulses
two groups of whales
odontocetes: toothed whales such as dolphins, proposes, orcas, belugas, narwhals, sperm whales, and beaked whales mysticetes: baleen whales such as humpback, grey, Northern right, Minke, fin whale
problems with studying fossils in Archean and Proterozoic (6)
old rocks are rare metamorphism and deformation have destroyed evidence of life in many old rocks well preserved ancient rocks are mostly located in unfortunate places only sedimentary rocks are likely to contain paleobiological evidence we are dealing entirely with extremely small microfossils relics of early life might be unrecognizable
Archaeopteryx
oldest bird skeleton Late Jurassic Germany found in 1860 and only 10 specimen less than .5 m, theropod with feathers didn't fly: sternum too small to support flight and adaptations that birds have to rotate their finger bones to change their position in the air were not there
Neoproterozoic Shelly Fossils (4)
oldest known mineralized animal fossils: Cloudina and Namaclathus appeared in late Ediacaran times composed of calcite up to an inch long grow in clusters forming small reefs
Relative age
one layer is older or younger than another; gives us no numbers
end ordovician mass extinction (3)
one of most severe mass extinctions few extinctions of higher order taxa (phyla, classes) coincident with major glaciation, sea level fall, organisms carbon burial (carbon isotope spike) resembles modern ice age (Pleistocene), similar extinction too
echolocation
only used by odontocetes series of sounds (clicks) bounce off objects and return to whale whales interpret to from a picture of size, shape and distance evolved early in whale history great example of convergent evolution same mechanism as in bats (alteration of a protein) sound originates in face rather than voice box
whales and dolphins
order cretacea evolved from land mammals in early Cenozoic all carnivorous
convergent evolution
organisms that are unrelated independently evolve similar structure or traits as a result of having to adapt to similar environments or ecological niches
Permian Triassic Mass Extinction: Lazarus Taxa
organisms that disappear from fossil record as if they're extinct but then reappear millions of years later refugia; places where the taxa could survive and show up in the fossil record coelacanth, brachiopods species, scleractinian corals
ordovician radiation (4)
phyla and classes radiated in cambrian, species numbers low until ordovician rapid increase in family, genus, and species number leveled off by late Ordovician unknown cause or causes
Dunkleosteus
placoderm fish that were powerfully built, jawed fish, head and thorax covered with bony armor, no true teeth carnivore late Devonian
Pleistocene flora
plants generally like today but distribution different spruce trees in Kansas evidence indicated forests not dense- probably scattered and confined to river bottoms
Taphonomy
process that preserves fossils
William Buckland
published first account on dinosaurs in 1824 found bones in England and didn't know what they were French scientist Georges Cuvier recognized them as a giant extinct reptile Buckland named it Megalosaurus
triassic
radiation of conifers
Jurassic Marine Plankton
radiation of shelly plankton changed sediment depositional locus to deep sea new rock types (chalk, chert) commonly affected sea water chemistry
Cretaceous Aerial Life (small and water)
rapid radiation of small birds in the Early Cretaceous and variety of water birds in the Late Cretaceous
vestigial structures
redundant organs that were functional in ancestors (appendix and whale leg bones)
Cretaceous Marine Life
reefs dominated by coral like bivalves: RUDISTS plankton mostly coccoliths formed chalk globally predatory nekton
Paleozoic reefs (3)
reefs: skeletal frameworks rising above sea floor up to 600 km long (Great Devonian Barrier Reef of Australia) constructing organisms varied over time but similar structure
difficultly of becoming terrestrial
reproduction everyone dependent on water for reproduction, amphibians lay eggs in water
Permian Triassic Mass extinction
resulted in loss of 95% of all marine species, 70% of terrestrial species exterminated many higher order class and order such as tabulate coral, trilobites, rugose corals
Archosauria
ruling reptiles group within diapsids differentiated from other diapsids by presence of single ant-orbital (in the front) fenestra among other characteristics crocodiles, flying reptiles, dinosaurs
Tyrannosaurid characteristics
s shaped neck to support the largest skull per body mass of any dinosaur eye sockets facing forward for binocular vision up to 60 teeth at any one time long heavy tail to counter balance the huge lead massive leg and feet bones small two fingered hand late cretaceous
limiting factors in MARINE habitats (3)
salinity, light, and for benthic organisms, substrate (kind of sea floor)
Ordovician marine life (3)
sea floor dominated by Paleozoic filter feeding fauna plankton mostly photosynthetic arcritarchs and filter feeding graptolites but jawless boneless fish (ostracoderms) and giant nautiloid cephalopods wireman predators
biologically induced biomineralization (4)
secondary precipitation of minerals due to metabolic by products results from interaction of organism and environment organism exerts no direct control over type and habit of mineral pyrite, calcite, magnetite
Devonian: Rise of Bony Fish
sharks with cartilage skeletons, small, 1 meter also lobe fin fish with apatite (CaPO4) bones
Odontocete skull
simple teeth compared with other mammals elongated snout big braincase and echolocation chamber next to the jaw joint (eye low on the skull and jaw joint far forward; nostrils moved way back to the top of the head, and exit the skull with a single opening aka blowhole)
Dromeosaurid characteristics
small carnivorous second toe has a large claw stiffened tail that provided balance and stability backwardly directing pubis long fingers with 3 fingered when and long claw
typical Cambrian fauna
small shelly fossils, trilobites, archaeocynathids by end of Cambrian, all animal phyla were present
amniotic egg
solution for reproduction protects embryo from desiccation enables animal to move away from water
habitat (2)
species: the natural environment in which a species lives population (community): the physical and biological environment that influences and is utilized by a community of organisms
archeocynathids (3)
sponges with simple cancerous skeleton consisting of a connected inner and outer wall lower Cambrian only main organism in the first of three major pulses in the Paleozoic reef building along with stromatolites
Cambrian radiation importance (3)
start of Cambrian 545 millions years ago sudden radiation of animals with. skeletons almost all phyla and most classes of shelly animals appear within 20 million years
homologous structures
structure that are embryologically similar but have different functions indicated that animals evolved from a common ancestor
how to solve problems of becoming terrestrial 5
support:cambium avoid destination: cuticle water and nutrient absorption: roots and stomata means of conducting water and nutrients throughout the plant: vascular system reproduction: spores and seeds
Gorgonipsids [paleozoic]
synapsid reptiles permian size of large bear
Jurassic Terrestrial Vertebrates
terrestrial animals dominated by dinosaurs arose in late Triassic herbivores common: Diplodocus, Seismosaurus, Stegosaurus
Diacodexis
the earliest whale ancestor closest modern relatives are pigs, war hogs, hippos...
Morganucodon
the first mammal? not sure but had many characteristics so many consider it a mammal Late Triassic, 205 mya
Ostracoderms
the first vertebrates jawless amored fish appeared in Early Cambrian
ecology
the interaction of organisms with their physical and biological environment
Quetzalcoatlus [mesozoic air]
the largest pterosaur 11-12 m wingspan walked on all fours
uniformitarianism
the present is the key to the past i.e. the same laws and processes the operated in the past operate now James Hutton, 1785
biomineralization definition and importance (3)
the process by which organisms form minerals critical because it gives structure and provides protection from predation allows better preservation and thus more complete fossil record
evidence from living organisms
the vertebrae: spinal column/axial skeleton the limbs...and many other morphological features can be compared
Impact of End Cretaceous Mass Extinction (together they parked dark cars with attractive rims)
thermal pulse, tsunamis, prolonged darkness, climate change wildfires acid rain act as killers recovery after extinction took 10 million years new faunas impoverished (few species), dwarfed
evidence from fossils
this necessitates the detailed placement of all whale fossils in relationship to each other (i.e. putting them in geological time order)
Sauropodamorpha
those that have sauropod body type largest land animals all herbivores Late Jurassic-Cretaceous Obligated quadrupeds, must walk on four legs
what happened to ediacaran fossils? (2)
thought to have gone extinct when animals with jaws evolved but some ediacaran like fossils in the Cambrian maybe unusual preservation style ended with advent widespread burrowing and crawling animals or perhaps evolution of scavengers destroyed carcasses before fossilization could occur
Terror Birds [cenozoic bird]
top predators of Miocene in South America 1-3 m tall run up to 48 mph may have migrated into Texas and Mexico after Istmus of Panama formed 3 mya Became extinct 1.8 mya
Ptersoaurs [mesozoic air]
triassic- cretaceous earlier vertebrates to evolve powered flight size of sparrow to size of small airplane carnivorous soaring as well as sustained powered flight
Dominant Cambrian fauna animals (7)
trilobites: declined over Paleozoic, extinct in Permian Triassic mass extinction benthic scavengers and nektonic predators grew by molting calcite apatite skeleton compound eyes some enrolled
problems of becoming terrestrial 4
unfriendly environment -everything is designed to live in water no support, everything would fall over need to avoid desiccation water and nutrient absorption a means of conducting water and nutrients throughout system reproduction
formation
unti or group of rocks that can be mapped on the Earths surface and recognized by its unique characteristics
paleoecology
using fossils and the rocks containing them to reconstruct ancient environments
Discovery of Pakicetus ankle
very different structure rom mesonychid anklebone with a double pulley for the tendons rather than a single one found unique double system evolved early and has not been shown to have reverted back to the single system
Sauropods characteristics
very long necks and tails with extra neck and tail verterbra erect pillar like limbs forelimbs shorter than hind limb but not a lot shorter very small lightweight skull vertebra have air sea to lighten structure
Neogene Marine Life
very similar to modern fauna whales and other marine mammals were major predators giant sharks
mysticete skeleton
vestigial hind limb, completely inside whales body
Cambrian fauna (3)
within 10 million years, diverse trilobites, brachiopods and reefs of archaeocyathan sponges first of 3 evolutionary faunas of marine animals dominate during Cambrian but then declined until disappearing during Permian Triassic extinction