Animal Phyla Flashcards
Porifera
Animals without tissues
Sponges
What type of body symmetry do sponges have?
Assymetrical or radial symmetric
How does a sponge gather food from their environment?
Filter feeding
How do the feeding mechanisms limit the kinds of food sponges can consume?
water drawn in through pores, contains bacteria and tiny particals, food in limited to smaller than the individual cells.
Eumetozoans and body symmetry
have true tissues which develop from distinct layers in the embryo.
Increase in complexity of functioning.
Radiata and bilatera
Radial symmetry
sense stimuli in all directions
life in open water
Cnidiria and ctenophora
Tissues but no organs or coelom
Diploblastic
Single opening - gastrovascular cavity with digestive and circulatory functions
gelatinous mesoglea btwn 2 layers
gas exhange and excretion via diffusion
cells cloase to body surface
Phyla Cnidiria
Mainly marine
Specialised cells for prey capture = cnidocytes with nematocysts
Polyps or medusa with tenticles tha surround the mouth
mesoglea and gatrovascular cavity differ in size
Simplest animals with specailsied tissues
Cnidirian digestion
Phagocytosis and intracellular digestion - vacuole
Digestive enzymes and extracellular digestion - gland cells
Cnidarian locomotion and hydrostatic skeleton
Skeleton = gastrovasular cavity in polyps and mesoglea in medusa’s
Locomotion = circular fibrils and longitudinal fibrils
Cnidiria lifecycle
Lifecycle can alter btwn polyp and medusa
polyp reporduces asexually
medusa reproduce sexually
4 cnidiria lineages/classes
Hydrozoa - polyp and medusa stages, polyps form sessile colonies
Scyphozoa - Jellyfish, bell shaped medusa
Cubozoa - box jellies, cube shaped medusa, poisonous toxin
Anthozoa - coral and anemones, sessile polyps
Bilateral Symmetry
Triploblastic
coelom or pseudocoelom
have organ systems
sensory organs = cephilisation
sister clades - Protosomia and deutersomia
Protosomes
Lophophorates = have a lophophore
circular or U shaped tentacles around mouth
gas exchange, feeding and excretion
sessile filter-feeders
coelomate and have complete digestive system
Marine animals
How do cnidirians capture, comsume and digest their prey?
Why is feeding more efficeint in cnidirians than protozoa even though there is still no digestive system?
which group of cnidirians only have a polyp stage?
Anthozoa
In which groups does the medusa stage predominate?
Hydrozoa, Cubozoa and Scyphozoa
How can cnidiarians and sponges complete bolily functions without organs?
Through diffusion
Phyla Plathelminthes
Aquatic environments
Acoelomate = no cloelom
No ciruclatory or respiratory organs = via diffusion
Plathelminthes ectoderm layer
Epidermis with ladder like nervous system,longitudinal ventral nerve chords and fibres
primitive brain=ganglioin
Eye spots in free living species
Flame cell system for excretory system.
Plathelminthes mesoderm layer
Forms the reproductive system and muscles
Plathelminthes endoderm layer
forms highly branched digestive system
One opening
Plathelminthes lineages/classes
Turbellaria - free living, with eyespots, food ingested and excreted through mouth, Hermaphroditic sexual reproduction, mostly asexual.
Trematoda - fluke, internal parasites in gut, liver, lungs, blood vessles of vertabrates. Complex life stages + multiple hosts
Monogenoidea - flukes, external parasites, gills or skin of aquatic vertabrates, single hosts, have suckers and hooks.
Cestoda - tapeworms, endoparasites, no digestive system, hooks and suckers, proglottids= repeating segements, contains reporductive systems.
why is it important that flatworms are only a few cm thick?
Body processes occur through diffusion
What organ systems are present in free living taxa?
reproductive systems and nervous system
Which system is absent from tapeworms?
Digestive system
How can tapeworms survive without digestive systems?
they are endoparasites that llive off of their hosts.
Phyla Mollusca
Visceral mass = reproductive, digestive, excretory, heart
Muscular foot
Well defined head, with sensory organs.
Sexual reproduction
Radula - drills through shells of prey, scrapes food together
Mantle - covers visceral mass
Open ciruclatory system = haemolymph (diffusion btwn nutrients and cells)
Seperate sexes
Mollusca lineages/classes
Polyplacophora - Chitons, oval, biltaeral, 8 plated shell, sedentary-graze on algea
Gastropoda - snails and slugs, aquatic have gills, terrestrial have lung, well developed head and sensory organs, tentecales have chemical touch receptors, cen see light intensity not colour. Herbivore and carnivore. BODY PLAN
Bivalvia - clam, oyters etc. enclosed in 2 shells, have reduced head, sensory organs can detect chemicals, touch anf light, statocysts can sense orientaion. sessile or sedentary.
Cephalopoda - active predators w/ larges eyes, octopus, squid, fused head and foot, tentacles, modified or absent shell, modified circulatory + sensory system, haemolymph, large brains
3 body regions common to mulluscs?
visceral mass
foot
head
name and describe the process in shelled gastropods that serves to provide space in the shell that the body can pull into
Torsion - reorganisation og body parts independantly of shell coiling
What anatomical structure and physiological systems allow squids to be much more active than other types of mollusks?
Modified circulatory system to increase the activity
How are these structures or system modified compared to other clades?
They have closed ciruclatory system = haemolymph confined within the walls of hearts and vessels.
Phylum annelida
(segmented worms)
organs and muscle organised into repeating segments, has longitudinal and cirular muscles for movement, chitin reinforced bristles, complete digestive systems, closed circulatory system, no respiratory system -diffusion of gasses, simple brain, ganglia in each segemnt, sensory organs, metanephidira - excretory system, sexual reproduction, hermaphrodites.
Annelid lineages/classes
Polycheate - Marine bristle worms, sedentary, burrows and tubes, filter feeders, predators and scavengers, weel developed prapodia.
Clitellata - oligocheate worms, terrestrial, earthworms, detrivores, clitellum; leeches, most modified, freshwater, blood sucking parasites, secrete hirudin to prevent blood clots.
What are the main distinguishing chracteristics of annelids
Segmented
Which organ systems exhibit segmentation in annelid worms?
excretion
why is segmentation so important in annelids?
Allows more efficeint movement.
ecdysozoan protostomes
protective external covering
reproduce sexually
Phyla: Nematoda, Onychophora, Anthropoda
Pylum Nematoda
Free living, break down organic materials and recycle nutrients, hook worms are important in digestion, parasitic species infect plant roots.
Roundworms = cyclindrical body, tapered at both ends, tough water resistant cuticle, move by alternating muscle contraction.
Organ systems = open circulatory, complete digestive, nervous system with ganglia and nerve chords, no respiratory system, sexual reproductin, seperate sexes.
Pylum Onychophora
velvet worms
live under stones and logs
Moist temp habitat
segemented bodeis
multiple papirs of excretory organs and unjointed legs
flexible cuticle, open circulatory system, specailised respiratory system, large brains, jaws, tiny claws
produce live young.
Phylum Arthropoda
Multiple jointed appendages
Rigid chitin exoskeleton
Body segments - no internal sepration, head, abdomen, thorax. Open ciruclatory system. Heart pumps haemolymph from haemocoel. Respiration varies by group. Complete digestive system. Cephilisation and organised CNS. Brain and nerve chord, touch receptors, chemical sensors, compound or simple eyes, hearing organs. Seperate sexes and internal fertilisation.
Advantages and disadvantage sof chiton exoskeleton
Advantages:
Protective
Attachment site for muscles
waterproof
Disadvantages:
Can’t expand, limits growth
oxygen cannot be taken up over skin
Arthropoda subphylums
Chelicerata
Myriapoda
Hexapoda
Crustaceans
Chelicerata
Arachnida + Merostomata
2 major body regions
appendages on head, chelicerae are fanglike structures used for biting prey, pedipapls serve in grasping, sensory organ or as legs, 4 pairs of walking legs, respiratory structures derived from appendages on abdomen.
Marine Chelicerates - horseshoe crabs, carnivorous bottom feeders in shallow coastal waters.
Terrestrial Chelicerates - Arachnida, spiders and scorpions, predators, mites feed on plants and animals, ticks feed on blood, important in agriculture and disease transmission.
Myriapoda
Centipedes and millipedes
terrestrial
2 body regions = head w/ antenae + trunk w/ many walking legs.
Madibles
centipedes have 1 pair of legs per segment, and are fast predators with toxins.
millipedes have 2 pairs of legs per segment, slow, herbivores or scavengers.
Crusteceans - aquatic
1 pair of mandibles and 2 pairs of maxillae
Decopoda + Copepoda + Ciriipedia
Decopoda - crabs, lobsters, shrimp. Marine animals. Extreme spcialisation of appendages.
Copepoda - small species, live as plankton. abundant, NB part of aquatic food webs.
Cirripedia - barnecles, sessile adults live in strong calcified shell. Filter feeders, hermaphroditic.
Hexapoda
Insecta
Diverse and succesfull animals on Earth.
Head had multiple mouth parts, compound eyes, sensory antenae.
Thorax has 3 pairs of walking legs, and 1 or 2 paris of wings. Wings made of chitin and sclerotin. Abdoemn includes much o fthe digestive system and part of reproductive system.
Gas exchange through tracheal system. Waste excretion through malpighian tubules.
Anthropoda lineages/classes
Trilobita
Earliest antrhtopods
extinct
Longitudinal grooves divide the body into 3 lobes
oviod, dorsoventrally flattened and heavily armoured.
3 body sections
head inclues a pair of chemosensory antenae and 2 compound eyes.
thorax and abdomen bear pairs of walking legs.
What are the insect sensory systems?
Compound eyes that form images
Light sensing ocelli
Chemical and touch receptors
hearing and sound producing organs.
Insect specialsied mouthparts
Mandible
Maxilea
Labium
Labrum
Wha are the developmental stages of insects?
No metemorphosis - no dramtic change
Incomplete metamorphosis - develop fro nymph into adult
Complete metamorphosis - total reorganization of internal and external anatomy (worm>pupae>fly)
Importance of anthropods
agriculture - destroy vetagble crops and stored food. Essential for pollination, some parasitic pests. Essential for food chains.
economy - some make silk, honey, wax
medical - transmit diseases, clean wounds and forensics.
What part of a parasitic nematode’s anatomy protects it from the digestive enzyme of its hosts?
They have a cuticle
Which characteristics of Onycophora are similar to Arthopoda and Annelida?
Annelida - segmented
Antropoda - Numerous pairs of legs
If an anthropods rigid exoskeleton cannot be expanded, how does the animal grow?
Grows via shedding thier exoskeleton and growing in size before their new exoskeleton hardens
How do the number of body regions and appendages on the head differ among the 4 groups of living anthropods?
Different mouthparts = maxila, mandible, labium and labrum
Have antennea
Different exoskeletons
How do the life stgaes differ btwn insects tha have a incomplete metamorphosis and those that have complete metamorhposis?
complete = complete internal and external rearrangement or organs
incomplete = develop from a nymph into an adult
Deuterosomes
Mouth develops from2nd hole during embryonic development
Radial cleavage
Enterocoelom
Phylum Echinodermata
Adults = Radial symmetry, slow moving/sessile
Larvae = bilateral, free swimming
Internal skeleton of calcium stiffened-ossicles
Starfish, sea urchins, sea cucumbers, feather stars, brittle stars.
Echinodermata anatomy
well defined coelom
complete digestive system
no excretory/respiratory system
no head no brain
reproduce sexually - release into water coloumn or asexually - split off and regenerate.
Echinodermata water system
locomotion
fluid filled canals
radial canal is connected to tube feet protruding through holes in ossicles
When ampulla contracts fluid is forced into foot = lengthens and grips
ampulla relaxes fluid forced out foot = shortens and releases grip
Echinoderm lineages/classes
Asteroidea - sea star central disk with radiating arms (crown of thorns eats coral)
Ophiuroidea - Brittle stars
central disk with long slender arms
Echinoidea - sea urchin and sand dollars
lack arms, have moveable spines. (aristotles lantern)
Holothuroidea - sea cucumbers
Long squishy fleshy body with a rough leathery covering
tube foot are modified to filter feed
gas exchange through branched respiratory tree
Crinoidea - sea lilies and feather stars.
upward pointed mouth surrounded by hundreds of arms.
Phylum Hemichordata
Acorn worms
sedentary marine animals
live in U shaped tunnels or burrows
Soft bodies - anteroir proboscis, tentacled collar and elongated trunk
Pairs of pharyngeal slits in pharynx that trap suspended food and exchange gases - coupling feeding with respiration
What organ system is unique to echinoderms, and what is its function?
Has a water vascular system with tubed feet
Why are echinoderms not part of radiata?
exhibit bilateral symmetry in developmental stages.
What are morphological characteristics shared by all groups in the echinodermata phylum?
Tubed feet
How does the perforated pharynx enable hemichordates to acquire food and oxygen from seawater?
They couple feeding and respiration by using their pharyngeal slits to trap suspended food and exchange gases.
Phylum Chordata
Notochord support embryo from head to tail and can bend left and right as muscles contract.
Segmented muscles in body wall and tail allow each muscle to contract independently.
dorsal hollow nerve chord forms a CNS with the ectoderm.
Perforated pharynx with outpocketings and perforation slits occur during some stage of the animals life cycle.
Chordata subphylums
Cephalochordata
Urochordata
Vertebrates
Cephalochordata
Lancelets
Elongated bodies, pointed at both ends
Cephilisation
Filter feeders and breath via the atrium (pouch around pharynx)
Urochordata
Tunicates
Swimming larvea have usual chordate features:
Mouth
Atriopore
Pharynx with slits
Gut
Dorsal hollow nerve chord
Segmental body wall and tail muscles
Notochord
Postnatal tail
Adult tunicates
Sessile with a “tunic”
Feed as lancelets (filter feed)
Vertebrate Characteristics
Internal skeleton provide internal structure support for muscles and protects the NS - enables rapid movement
Only animals that have bone = secreted by living cells
Axial skeleton = vertebral column made up of individual vertebrea surrounds and protect dorsal nerve chord. Bony cranium surrounds brain. Ribs and sternum protects internal organs
Appendicular skeleton = Anterior pectoral girdle (arms) and posterior pelvic girlde (hips and legs)
Neural crest cells = arise next to developing NS, contribute to unique vertebral stuctures, teeth, sensory organs, cranial nerves, anterior medulla of adrenal glands.
Large complex brain = brain split into 3 regions - forebrain; midbrain and hindbrain - govern a distinct NS function.
Pharynx = suck water into mouth, is more efficeint than cilia.
What structures distinguish a vertebrate from an invertebrate chordates?
Internal skeletons
Early vertebrates
Fibrous cranium and segmented body-wall muscles.
No bones
Chordate phlogeny
Craniate vs. Vertebrates
Agnathans - jawless vertebrates
Gnathostomata - Jawed fish and tetrapods
Which taxonomic groups Amniota, Gnathostomata and tetrapoda includes the larges number of species?
And Which incluede the fewest?
- Tetrapods
2.
Living agnathans
Hagfish and lampreys
Jawless fish:
Have a well developed cranium, notochord and cartiligenous skeletons.
No true vertebrae, paired fins or scales
Hagfish
No specailised structures surrounding the dorsal nerve chord
Scavengers
Lampreys
Dorsally pointing cartilages that partially cover the nerve chord
Parasites
Extinct Agnathans
Conodonts and ostracoderms
Conodonts
Elongated soft bodied animals with a notochord, cranium, segmenteal body wall muscles, large moveable eyes
Bonelike feeding structures made of dentine
10cm long
Ostracoderms
Amoured skin with bony plates and scales
some had fin-like extentions
Muscular pharynx improved feeding and breathing efficiency
No true vertebral column, but had basic support structures around nerve chord and brain
2m
What characteristics of the living hagfish and lampreys suggest that their lineages arose very early on vertebral evolution?
They do not have a true vertebral column
What traits in conodonts and ostracoderms are derived relative to those in hagfish and lampreys?
The Evolution of Jaws
Gnathostoma
Jaws = greatest advance in evolution
Increased feeding efficiency
Defense
Grooming
Nest construction
Transport of young
Evolution of fins
Moveable fins
Paired and unpaired
stabalized locomotion
and deterred predators
Annual, dorsal and caunul fin for stabiliy
Pectoral and pelvic fins for steering
Caudel fin for power and thrust.
Why was the development of jaws and fins so important?
Increased feeding flexibility and effciency
Increase in diet diveristy
More food = bigger individuals
Moveable fins increased agility in movement.
Extinct gnathostomes
Upper jaws firmly attached to cranium
Inflexible mouths and internal skeleton
Class Chondricytes
= cartiligenous fish with skeletons compsed entirely of cartilage
Subclass Elasmobranchii - Skates and rays dorsoventrally flattened
Shaks are streamlined, dominant predators with flexible fins, lightweight skeletons and bouyant livers which increase the swimming efficiency. No gill cover less efficient breathing.
Elasmobranch feeding adaptions
Improved feeding - teeth develop in rows new teeth migrate forwards. `upper law loosely attached to cranium. Modified digestive system to improve digesting efficiency.
Improved sensory systems to detect prey - Vision and olfaction. Electroreceptors detect weak electric currents produced by prey. Lateral-line system tiny sensors in canals along both sides of the body detects vibrations in water.
Elasmobranch reproduction
Internal fertilisation
Different types of embryo nourishing:
Produce large yolky eggs with tough shells
Retain eggs within oviduct until young hatch
Nourish young in the uterus.
What characterisitc of sharks and rays make them more efficient predators than acanthodian and placoderms?
Why is the cartiligenous skeleton considered derived and not ancesteral?
Why is evolution of jaws considered such and important advancement in evolution of vertebrates?
Jaws = greatest advance in evolution
Increased feeding efficiency
Defense
Grooming
Nest construction
Transport of young
Increase in diet diveristy
More food = bigger individuals
Osteichthyes
Bony fish
fish with bond endoskeletons = most successful vertebrates
strong light bones
moveable fins
light scales and mucus
swim bladder
operculum (gill cover)
Classes:
Actinopterygii - ray finned fish, fins supported by by thin, flexible bony rays.
Sacropterygii - fleshy-finned fish, fins supported by muscles and internalebony skeleton
Actinopterygii
most primititve lineages (sturgeons)
cartiligenous skeletons
Teleosts:
Latest radiation most diverse , successful and familiar bony fish. Sensory systems. Vision olfaction, lateral line system, sound receptors for hearing. Gas-filled swim bladder derived from ancesteral air-breathing lung = inceases bouyancy. Internal skeleton almost entirely of bone. Modified jaws enable different diet. Operculum covers gill chamber and improves breathing efficiency. fins for imrpoved locomotion - getting food, courtship, and caring for young. Body is covered in scales and mucus
Teleost reproduction
Marine fish:
Produce planktonic larvae - eggs are fertillised and hatch in water.
Fresh water fish:
direct development - eggs hatch into fish, sometimes give birth to live young.
Sacropterygii
Lobe-finned fish - 2 marine species of coelecanths, live at 70-600m depths
Lungfish - 6 freshwater species on southern continents, their lungs may supplement or replace gill respiration when oxygen concentration is low.
How do the air bladder and funs of ray-finned bony fish increase their locomotor abilities?
How do the lungs of lungfish allow them to survive in stressful environments?
When oxygen is low their lungs supplement or replace gill respiration.
Tetrapoda - the evolution of limbs
transition from water to land
air provides less support for an animal’s body.
Air causes loss of body water via evaporation.
sensory systems of fish do not function well in the air.
Why bother leaving water?
swampy environments have a high moisture (humidity)
lots of oxygen, food
few predators
warmer conditions increase the metabolic rate
better performance.
early tetrapods
probable anscestor to tetrapods
common characteristics:
Strong fins and supportive vertebral column
Nostrils and olfactory receptors
Lungs
Acanthosestega
well anchored pelvis
could hear in air - tympanum vibrated by airborne sounds, stapes transfer vibrations to sensory cells of an inner ear.
Fishlike characteristics:
general body form
large caudal fin
operculum
Tetrapod characteristics:
well-defined fingers and toes sturdy vertebral column with ribs
well-anchored pelvis
Transition species (water to land)
Tiktaalik
Fishlike characteristics:
bony scales
fins
gils and air-breathing lungs
Tetrapod characteristics:
Have a neck, well-developed ribs
Forelimbs with humerus
radius and ulna
robust pelvis fins
flattened skull with upward-pointing eyes
Tetrapoda
First tetrapods were amphibians
Living amphibians are smaller and have fewer bones than early tetrapods.
Classes of Tetrapoda
Amphibia
Amphibia
Adults are aquatic, amphibious, or terrestrial.
Most have thin moist skin - main breathing site, some adults have sac-like lungs.
Eggs are laid into water an hatch into larvea/tadpoles undergo metamorphosis develop into adults. Some are paedomorphic.
Orders:
Anura = short compact bodies, long legs w/ webbed feet, adults lack tails. (frogs)
Caudata = elongate, tailed body with 4 legs, most live in water (newts)
gymnophoina = legless borrowers with wormlike bodies, internal fertilization, give birth to live young (caecilians)
For early tetrapods what were the advantages and disadvantages of moving onto land?
Advantages:
lots of oxygen, food
few predators
better performance.
Disadvantages:
swampy environments have a high moisture (humidity)
warmer conditions increase the metabolic rate
air provides less support for an animal’s body.
Air causes loss of body water via evaporation.
Which characteristics preadapted osteolepiform for life on land?
Which fish-like and tetrapod-like characteristics were present in the transition and early tetrapod species?
Which parts of the life cycle in most modern amphibians depend on water or very moist habitats?
Larval stage
Besides for reproduction, why do many amphibians still need to remain near or in water?
Most have thin moist skin - main breathing site.
Amniotic egg
Amnion - fluid-filled sac surrounding the embryo
Modern reptiles and birds:
Shell
Yolk - energy source
Albumin - source of nutrients and water
Most mammals:
No shell
embryo’s implant in the wall of the uterus and receive nutrients and oxygen from the mother.
What adaption allow the amniotes to live on dry land?
tough, waterproof skin containing keratin and lipids, prevent dehydration.
Semisolid uric acid as a waste product of nitrogen metabolism.
Amniote eggs that survive and develop on dry land.
2 Amniote lineages
Synapsida Mammals and their Ancestors:
Glandular skin
fur or hair
give birth to live young
Nourished by milk
endothermic
Reptilia:
everything else
scalely, non-glandular skin
eggs of most can only survive on land
don’t produce milk
ecto- or endothermic
How did the evolution of the amniote egg free amniotes from a dependence on standing water?
tough, waterproof skin containing keratin and lipids, prevent dehydration.
Semisolid uric acid as a waste product of nitrogen metabolism.
Amniote eggs that survive and develop on dry land.
What groups of animals are included in each of the 2 major amniote lineages?
Reptiles and synapsida mammals
Lineages of reptiles
Lepidosaurs - 2 extinct marine groups, 2 extant terrestrial groups.
Archelosaurs - 3 extinct groups, 3 extant groups.
Living lepidosaurs
Oders: Sphenodontia and Squamta
SPhenodontids:
Lizard shaped animals living on island off new zealnad coast
60cm long
Live in colonies
CArnivourous
Active at night
Squamates
Lizards and snakes
Overlapping keratinized scales prevent dehydration
Periodically shed their skin as they grow
Regulate their body temp behavior (Poikilotherms and ectotherms)
LIzards: 15cm-3m
A wide range of habitats common in deserts and tropics
Dinural
feeds on insects and meat.
Snakes:
Predators swallow prey whole
Skull bones are connected by elastic ligaments
Kill prey via construction or venom
systems for detecting prey = sensory receptors in the roof of the mouth and heat-sensing organs
Based on the evolutionary history of the amniotes, are crocodilians more closely related to lizards are birds?
How do lizards and snakes differ?
living archelosaurs
Orders:
Testidunata - tortoises and turtles
Crocodilia - crocodiles and alligators
Aves - birds
Testudines
Bony, boxlike shell
Ribs are fused to carpace
Pectoral and pelvic girdle lie within the ribcage - allows space for the turtle to pull its head into its shell
Large keratinized scales over the bony plates of the shell
Terrestrial, freshwater and marine species
Lack teeth
Herbivore and carnivore.
Anatomical adaptions andd behaviour distinguish them from living lepidosaurs and testudines
Four way chambered heart - more efficient blood pumping, oxygen poor and rich blood will never mix
One way air flow
Maternal care of young
MOdern Birds
Classified in to 30 groups
from 1g to 15okg
Structure of the bill reflects the bird diet
CArnivourous birds have a sharp bill
Duck have bills modified to extract particles from water
Necter-feeding birds have a long bill
Seed and nut eaters have deep stout bills
Birds also differ in feet structure and wings. Predators have large strong talons
Ducks have webbed feet
Long-distance fliers have narrow wings
Birds that hover at flower have a wide wings
Wings of penguins are so specialized that they cannot fly.
adaptions fro powered flight?
Skeleton:
Strong and lightweight with hollow limb bones.
Fewer individual bones in the wings,, skulla nd vertebral column.
Large flight bones qad massive flight muscles attached to keeled sternum..
Muscles accommodated for flight = Pectoralis Major and Supracoracoideus.
Feathers:
Derived from scales
Sturdy and light
Flight - feathers on wings, provide lift.
Contour - feathers streamline the surface of the body
Down- feathers that are insulating cover close to the skin for heat.
Reduced Body weight:
NO bladder or teeth
Single ovary - 1 mature egg laid as soon as they are shelled.
Metabolic adaptions:
High metabolic rate
Efficient consumption and distribution of oxygen
One way flow-through system
4 chambered heart.
Crocodilia
Semi-aquatic predators - eat other vertabrates
Nile Crocodile
Bird diversification
earliest bird = archaeopteryx, had feathers and dinosaur skeleton. Digits and claws on forelimbs, teeth on jaws, many bones in wings and vertebral column, poorly developed sternum, birds with full flight capacity appear 140mya. All modern birds represented by 23mya
Fujianvenator prodigious = discovered in China 2022 same age as archaeopteryx, long legs for running or wading.
Aves
Birds
Feathered archosaurs wit no teeth
ligtweight
Keratinized bill - feeding, grooming, nest-building, and social interactions.
HOw does the overall structure of turtles distinguish them from other amniotes?
Pelvic and pectoral girdle is inside thier ribcage, which allows space for their head and legs to be contracted into their shells.
Bird behaviour and migration
weell-developed sensory system nd NS and proportionally large brains
Migators used polarized light t, changes in air pressure and sun and stars and Earth’s magnetic field for orientation.
Long-distance migration in response to seasonal changes in the climate.
Most birds have complex social behaviour, including courtship, territory, and parental care.
What anatomical and behavioural characteristics of crocodilians demonstrates their relatively close relationship to birds?
What specific adaptions allow birds to fly?
Skeleton
feathers
Metabolism adaptions and reduced body weight.
Synapsida Mammalia
2 mammalian lineages
Prototheria and Theria
HOw do the structures of birds bills, wings, and feet reflect its dietray and habitat specializations?
Key adaptions of Mammalia
High metabolic rate and temperature = maintain high activity levels. 4 chambered hearts. Complex circulatory systems. Diaphragms. Fur and subcutaneous fat.
Specializations of teeth and jaws = increase feeding efficiency. Incisors, canines, premolars and molars. Teeth of upper and lower jaw occlude.
Parental care = development within the mother’s uterus, deriving nourishment through the placenta. Mammary glands produce energy-rich milk.
Complex brains = are responsible for processing information. Influences behaviour.
Metatheria
Marsupials, pouched animals.
Kangaroos, opossums. Mainly in Australia.
Have a similar ecology to Eutherian placentas.
Prototheria
Egg layers
% living species
1 duck-billed platypus, 4 echidnas
Only in Australia
Leathery shelled egg
Milk is secreted by modified sweat glands on the stomach.
theria
live bearing
Eutheria
placental mammals
Have highly specialized limbs
Flipper and wings
Diverse diets
Insectivores; herbivores; carnivores; frugivores; nectivores; omnivores.
Reproductive strategies of theria
Marsupials complete embryonic development attached to a teat in the mother’s pouch
Placental complete embryonic development in the mother’s uterus, nourished through the placenta until the advancement stage of development. Duration and gestation depend on the size of the animal. Newborns may be altricial or precocious.
Why are most mammals active only during the night until 65mya?
Which key adaptions in mammals allow them to be active under many types of environmental conditions?
High metabolic rates with specializations
Parental care
complex brains.
Primates derived traits enable tree-dwelling lifestyle:
Erect postures
Flexible joints
Gasping hands and feet
nails not claws
Opposable thumbs
Fingetips with sensory nerves.
Priamtes key derived traits
Dinural
Rely on vison not smell
Forward acing eyes
Overlapping field of colour vision
Complex social behaviour
Large, complex brains
Small broods with extended parental care.
Primate phylogeny
Strepsirhini - Moist, fleshy noses, eyes lateral on head.
Haplorhini - compact, dry noses, forward facing eyes
Tarsiers - small bodied, large eyes and ears.
Anthopiods - monkeys, apes and humans
Anthropoidea
Contiental drift seperated anthropiods into old and new world monkeys
New world monkeys
Americas
Arboreal and dinural
larger species hang by their arms, using a prehensile (grasping) tail.
On what basis are the three major groups of living mammals distinguished?
The parental care.
Marsupials or placentals or live-bearing.
Old world monkeys
Africa and asia
May be arboreal or walk on the ground
don’t have prehensile tails
Sexually dimorphic.
Hominoidea
Arboreal
dryer and cooler woodlands and forests
Apes lack tails
great apes are larger than monkeys
Stable vertebral column
Complex social behaviour
Gibbons - long arms, move via brachiation
Orangutans - use hands and feet for climbing
Gorillas - Live in forests, knuckle walk
Chimps - live in forests, knuckle walk or bipedal swaggering
Humans
Live everywhere
Adaptions for upright posture and bipedal walking
specialized for other activities.
What characteristics of primates allow them to spend much time in trees? How did these contribute to their adaptions to an arboreal lifestyle?
Erect postures
Flexible joints
Gasping hands and feet
nails, not claws
Opposable thumbs
Fingertips with sensory nerves.
Which primitive characteristics are retained by the Strepsirhini and Tarsiers, respectively?
Strepsirhines retain more primitive characteristics.
Tarsiers retain primitive features such as grooming claws and an unfused mandibular symphysis
What is the lowest taxonomic group that includes monkeys, apes, and humans?
Primate
What are the main differences between apes and monkeys?
Apes don’t have tails and are much larger than monkeys.
What is the lowest taxonomic group that includes only apes and humans?
Hominoidae
