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Everything Else Flashcards

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0
Q

Tunicates (urochordata)

A

Sea squirts,
larvae are free swimming
Adults are sessile

pump water using two siphons

shows most of major chordates like a notochord

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1
Q

Lancelets (cephalochordate)

A

Small eel like animals

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2
Q

Sister groups to vertebrates

A

Tunicates and lancelates

Lancelates most likely related to vertebrates

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3
Q

Fishes- what are they

A

All vertebrates excluding tetrapods

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4
Q

Agnatha- what are they and when were they diverse

A

Jawless fishes

Diverse in the Paleozoic. Only two living groups

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5
Q

Gnathostomata

A

Jawed fishes

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6
Q

Hagfish

A

One of two living jawless fishes

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7
Q

Lampreys

A

One of two jawless fishes

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8
Q

Chondrichthyes

A

Sharks and rays

Not bony. Have cartilage only

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9
Q

Osteichthyes

A

Bony fishes. Have scales that articulate (makes for fairly flexible but rigid trunk that aids in swimming) and overlap

Internal swim bladder

Well ossified internal bony skeleton

Large variety of body forms and morphology

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10
Q

Actinopterygii

A

Ray finned fishes
Bulk of diversity of fishes- teleost fishes

Found in any water habitat

Teleost fishes have uroneurals- bones in the tail that stiffen the doral lobe of the tail and support dorsal fin rays—gives them greater swimming power

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11
Q

Dipnoi

A

Lung fishes

Diverse during Paleozoic and Mesozoic

Only 3 genera survive in Southern Hemisphere

Evolved ability to breathe air

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12
Q

Crossopterygii

A

Lobe finned fishes

Large predators during Devonian

Now at least two known species

First specimen of coelacanth discovered in 1938 in s Africa

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13
Q

Coelacanth

A

Two species currently known

In western Indian Ocean and Indonesia

Deep water habitats

Opportunistic bottom drift feeder. Feed on other fishes, Cephalopods etc

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14
Q

Causes of cichlid radiation

A

Old hypothesis: speciation resulted in isolation in smaller lakes around lake Victoria

Problems: satellite lakes only have a few species and so cannot explain the bulk of diversity

Sexual selection driving speciation

Females choose the males. Males only have color. Maintains reproductive isolation between species

Cannot explain “rock” species - each group of rock islands in Victoria has it’s own species assemblage but satellites have no rocky islands

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15
Q

Decline of native freshwater fishes

A

Overfishing

Pollution and agricultural runoff- water gets murkier, females can’t tell the color of males, so species barriers break down

Introductions of exotic species - tilapia into lake Victoria

Intro of Nile perch. Then it went thru a population explosion, which caused decline in native fish diversity

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16
Q

Causes of cichlid radiation - old hypothesis? problems with that hypothesis?

A

Old hypothesis: speciation resulted in isolation in smaller lakes around lake Victoria

Problems: satellite lakes only have a few species and so cannot explain the bulk of diversity

Sexual selection driving speciation

Females choose the males. Males only have color. Maintains reproductive isolation between species

Cannot explain “rock” species - each group of rock islands in Victoria has it’s own species assemblage but satellites have no rocky islands

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17
Q

Ichthyostega

A

Earliest known land vertebrate til tiltaalik was discovered

Fish like fin rays, notochord entering braincase

7 digits on hind limb

Skull and ankle bones unique and different from other

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18
Q

Living amphibians - lissamphibia

A

Monophyletic with 7000 living species

Three main groups:
Anura/tail less amphibians - frogs and toads are the largest group

Urodele/Caudata- newts and salamanders

Caecilians- limb less

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19
Q

Ichthyostega

A

Earliest known land vertebrate til tiltaalik was discovered

Fish like fin rays, notochord entering braincase

7 digits on hind limb

Skull and ankle bones unique and different from other tetrapods

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20
Q

Causes of global amphibian declines

A

Introduced species

Various pathogens - fungal, bacterial, viral

Increased UVB radiation

Habitat destruction

Climate change

Exploitation- sold as food pets

Pollution and pesticides

Synergies - interaction between UVB radiation , climate fluctuation, and parasitic infection

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22
Q

Anapsids (an amniote)

A

Turtles

Skull has no opening in the back of the skull

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23
Q

Synapsids (an amniote)

A

Led to mammals

One opening in back of skull

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23
Q

Function of openings in back of skull (temporal openings)

A

Reduces concentration of mechanical stress in the skull

Room for increased attachment and bulging of jaw muscles

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24
Diapsids (an amniote)
Rest of reptiles including dinosaurs and birds Two openings in back of skull
26
Reptiles
Highest diversity of group during Mesozoic - dominant, terrestrial and aerial, some marine major extinction during K-T mass extinction
27
Lake Malawi in africa - how many major clades?
Lake Malawi - has two major clades
28
Lake Victoria - how many major clades?
one
29
Cichlids and Cyprinids - which is more diverse and where is each found?
Cichlids more diverse and found in lakes | Cyprinids found in rivers
30
tiktaalik rosae - what are its tetrapod traits
Tetrapod traits- neck: head and shoulders differentiated- could move it's head around on neck Ribs- had a full set. Was air breathing and supported body Head was much flatter compared to fish with eyes on top of skull like crocodile Tiktallik couldn't walk but the front fins could support weight
31
two major groups of diapsids
archosaurs and lepidosaurs
32
Lineages of archosaurs
pseudosuchia - crocodiles and relatives ornithosuchia - dinosaurs and birds
33
lineage of lepidosaurs
squamata - lizards, snakes, etc
34
major groups of turtles
pleurodira and cryptodira sister groups; represent an old split
35
Pleurodira
turtle group horizontal contraction and folding of neck in s. hemisphere in fresh water
36
Cryptodira
turtle group vertical contraction of neck absent in s. hemisphere
37
examples of reptiles
turtles, alligators, crocodiles, gavialidae, sphenodontidae
38
squamata
5 main lineages: iguanius, gekkotans, amphisbaenians, autarcoglossan, snakes so many body forms - more than tetrapods anaconda - gecko live everywhere except antarctica
39
Major groups of Diapsids
Archosaurs and Lepidosaurs
40
Lineages of Archosaurs
Archosaurs are a monophyletic group with two lineages - Pseudosuchia and Ornithosuchia
41
Pseudosuchia
crocodiles and relatives
42
Ornithosuchia
dinosaurs and birds
43
Ornithscians
included herbivores like stegosaurs, hadrosaurs, and ceratopsians
44
Saurischians
two major lineages are sauropods and theropods (coelusaurs - tyrannosaurs, dromaeosaurs, birds)
45
Archaeopteryx - what is it? what are its characteristics?
a bird that has qualities of both a bird and a dinosaur/reptile Characteristics: - 0.5 meters long - combination of feathers and -reptilian traits - skull triangular but with large eyes and teeth - long tail lined with feathers - limbs with claws - feet with 3 toes in front and one in the back - bones hollow - feathers well developed
46
Feathers of birds - what are they? Types of feathers? Why did they evolve?
Complex structures made of a unique form of keratin Types of feathers: contour feathers, down feathers, semiplumes, filoplumes, bristles Feathers evolved in dinosaurs most likely for insulation
47
The avian skull - characteristics
Early birds had reptilian teeth in the jaw, but their teeth were lost over time, so teeth absent in all modern birds - toothed jaw evolved into the beak - beaks of living birds covered with a keratinized material - skull as a whole is reptilian but with much larger brain and eyes - avian brain tightly fills the brain case - not true for reptiles - all or part of upper jaw moves relative to braincase - unique feature
48
Muscular Gizzard - what is it used for
Since birds don't have teeth, they need another way to break down food the gizzard does this for them -grinding is often augmented by ingestion of grit and stones
49
Pneumatic bones - what are they
bones in birds that are hollow and very light but with an internal set of buttresses that make them strong
50
Skeletal rigidity in birds - how is it produced?
avian body is very compact and rigid. | it is produced by fusing many bones in the skull and elsewhere
51
sternum of birds - how is it improved for them
keeled and highly modified to accommodate expensive flight muscles keel provides a large area for muscle attachment `
52
Flight muslces of birds - which ones are they and what do they do
Supracoracoideus - raises the wing when it contracts pectoralis - much larger and provides the downward stroke in flight combined, these two muscles can account for ~35% of body weight of some birds
53
Carpometacarpus - what is it
a unique structure formed by the fusion of wrist and hand bones in modern birds
54
Distinctive characteristics of bird feet
3 in the front, one in the back - the perching foot the 5th toe is lost. but its present in reptiles
55
Types of avian wings?`
1. elliptical wings - short and broad; most passerines, doves, woodpeckers 2. high-speed wings - elongate; swifts, swallows, falcons 3. high aspect ratio wings - ideal for gliding; albatross, other seabirds 4. slotted soaring wings - vultures, eagles, storks
56
Arboreal origin of flight - what is it? what are problems of this hypothesis?
Gliding as a precursor to flapping of powered flight Problems: - adaptations for gliding and flapping flight are very different - in flying squirrels and flying lemurs, the proximal elements of the limb are enlarged - but in birds, distal elements are enlarged - in general, bird limbs are closer to adaptation for terrestrial locomotion than gliding
57
Cursorial origin of avian flight - what is it? what are problems of this hypothesis?
From running along the ground to flying Problem: its not clear how biomechanically feasible this hypothesis is. In particular, running to flight transition is problematic
58
Wing-assisted incline running (WAR) - what is it?
Running and flapping at the same time on an incline led to eventual flight the most likely hypothesis for origin of flight
59
Loss of flight in birds - how does this happen?
Flightlessness has evolved in many bird lineages at different times - associated with situations favoring selection for large body size - common situation in isolated oceanic islands without predators
60
morphological changes associated with loss of flight
size increases in most cases keel or sternum is reduced/lost muscles and bones of wing and pectoral girdle are reduced or lost flight muscles are lost feathers tend to degenerate
61
Extinction of birds on islands
correlated with arrival of humans largely due to predation by humans and introduced animals - rats, dogs, pigs pacific islands heavily impacted
62
Living Mammals vs Reptiles
Mammals: endothermic homeotherm Reptiles: ectothermic poikilotherm Mammals: 1 bone in lower jaw (3 missing bones evolved into middle ear) Reptiles: 4 bones in lower jaw Mammals: teeth not replaced continuously Reptiles: replaced often Mammals: brain much enlarged and specialized new forebrain structure Neocortex suckling and milk production
63
Early synapsids divided into 2 lineages
Pelycosaurs and Therapsids
64
Pelycosaurs - characteristics; how were they linked to mammals?
Reptile look alike had long/tall neural spines embedded in tissue = more surface area/used for thermoregulation The only trait linking mammals and pelycoaurs is the synapsid condition
65
Therapsids - characteristics; how are they linked to mammals?
They are more advanced, and is the real stem group to mammals included both carnivores and herbivores one lineage - cynodonts - led to mammals
66
Hadrocodium - what is it
the extinct group most closely related to living mammals
67
Three groups of living mammals
Monotremes, Marsupials, and Eutherians
68
Mammalian traits and reptilian traits of monotremes; examples of monotremes
Mammalian traits: - single bone in lower jaw - 3 inner ear bones - hair - milk production - high metabolic rate Reptilian traits: - egg laying, no live birth - primitive shoulder girdle - skull with many reptilian characters - cloaca present - no external ears platypus, anteaters - all restricted to Australia and new guinea
69
What are some characteristics of a platypus?
- have a coat of fur - aquatic - females lactate yet lay eggs - males have venom similar to reptiles - genome is a mix of reptiles and mammals - milk protein genes are conserved despite egg laying
70
Characteristics of Marsupials; examples of Marsupials
- live birth but short gestation times - born as larval animals - develop in moms pouch - brain small relative to eutherians - well developed sagittal crest for attachment of jaw muscles - number of teeth variable and different from Eutherians opposum, tasmanian wolf, tasmanian devil, dasyurus, parameloids (bandicoots), diprotodonts (koalas, wallabies, kangaroos,etc)
71
Megafauna in deep sea
Fishes known from 7.2 km depth; most have lost swim bladders & are negatively buoyant sessile megafauna: Mushroom coral, anemone, sea pens
72
Possbile causes of deep sea diversity
1. Stability-time hypothesis: constant environment → stable ! !biological interactions → specialization Lack of disturbance → microhabitats (complex burrows) 2. Biological disturbance: predation by megafauna reduces competition among macrofauna → coexistance Macrofauna in turn crops meiofauna 3. Patchy food resources: food-falls are generally patchy and can support high species diversity 4. Large area: Depths > 1000m cover 3 X 10 8 sq. km in world oceans. Large area should be able to support many species
73
Source-sink hypothesis for abyssal diversity
none of the deep sea species are endemic to that area- theory is that they migrated / sink down to abyss
74
anthropogenic impacts on deep sea - disposal
sewage, pharmaceuticals, co2, wrecks, clinker
75
anthropogenic impacts on deep sea - exploitation
fishing, mining, pipelines, science, ghost fishing, oil and gas,
76
anthropogenic impacts on deep sea - ocean acidification and climate change
warming temps, hypoxia, nutrient loading, stratification, ocean acidification
77
Causes of small geographic ranges for species
Speciation/extinction dynamics Ecological effects - Habitat specialization, physiological tolerances etc. historical effects
78
physical factors that limit geographic ranges
1. Physical: Barriers - mountains, ocean, etc Temperature - some evinroments are beyond physiological limits seasonality - ocean currents, salinity, hot summer, cold winter 2. Absence of suitable habitats 3. biotic interatcion - predators, competition, mutualism 4. Adaptation and gene flow - local adaptation (outward) and gene flow (inward)
79
Dispersion and vicariance
Dispersion - species first evolves, then actively moves across a barrier to a different area and from here they diverge A--> B --> C Vicariance - the species didnt actually actively move; they were separated somehow, maybe from tectonic activity, to a different area, and the group that got moved away formed a diff species B - formations of barriers is what separated the species, not the species moving
80
2 ways to be endemic
originate in an area and never disperse range collapse

Biodiversity (2 decks)

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