BIOL
How might the opening of the Tasman Sea and the subsequent separation of Zealandia (the landmass that included New Zealand and New Caledonia) from eastern Gondwana (Australia + Antarctica) approximately 120-80 million years ago be linked to a series of earth quakes off the coast of K'gari/Fraser Island, south-eastern Queensland during August 2015? Use a diagram to help explain your answer.
*figure out ask friendS!
Australian Rivers: Changing
- 65% runoff in northern Tropics - Australia has the most variable inter-annual rainfall = droughts and floods - any rivers very dry until a flood occurs
Thylacine
- Dingo's killed off through most of Australia - Still lived in Tasmania since no dingos - when Europeans arrived to Tassy they thought dingo's kind of looked like thylacines and they were worried the thylacines were killing their sheep - put warrant on thylacines - killed all, last one died in zoo
How do aquatic Fauna persist in desert habitats?
- Not all waterholes go dry at the same time - Low grade (slope) allows water to sit for a long time - Many species have dormant life stages
Lecture Ants n things 2 invasive ant types Au.
- Red imported fire ant in Queensland - Yellow crazy ant Christmas Island, Northern Territory, Queensland = invasive (tramp) ants
The driving force of climate
- basic imbalance in energy distribution - sun hits different parts of earth differently
Dasyuromorpha
- carnivorous marsupials - tassie devil - she - thylacine (extant)
Orographic rainfall
- moisture bearing winds forced to move up because of physical barrier like mountain - expand and cool as they rise up slope of fountain and upon further cooling they form clouds - as clouds become dense rain falls (windward side) receives most of rain and leeward side receives little rain as air falls and warms.
Chiroptera (bats)
- most diverse order of mammals after rodents Some species are found over much of the world, others are very restricted • Two suborders - Megachiroptera ('megabats') • Flying foxes/Fruit bats - Microchiroptera ('microbats') • Insectivorous and carnivorous bats - mega bats (8 species) - Microbats (
The Tweed Volcano Sheila formation Weathering
- mt. Waring Intruding the Tweed Present day Lamington Plateau • Tough, crystalline rocks of the vents and magma chamber are exposed as Mt Warning (Wollumbin) • Basalt flows lie beneath the eroded flanks • Nutrient-rich soils from the eroded basalts support dense sub-tropical rainforest Shield formation • The Gold Coast Hinterland passes over the East Australian hotspot • Flows of basalt, rhyolite and other volcanic materials erupt to form a collosal shield volcano, 2 km high and over 100 km in diameter Weathering • The volcano draws rain-bearing clouds to its dormant bulk • Streams cut into the volcano's flanks, exposing basalt and rhyolite lavas • Erosion is most rapid along the high-rainfall eastern side
How do the feet of passerine (perching) birds differ from the feet of other birds? Why is the foot of a passerine better suited to perching than other types of bird feet? Use diagrams to help explain your answer. (2 marks)
- they have 3 forward toes and one backwards at same level of forwards - A tendon in the rear of the leg makes the foot curl and grip when the bird lands on a branch. This is more than just a convenience for the birds: it is a locking mechanism so they can sleep without falling off.
3 main types of rocks
1. Igneous - volcanic (cools after erupting) or plutonic rocks (cools below surface, can be any age but if exposed it is generally old) i.e. volcanic - basalt, plutonic = granite - primary source of all rocks at earth's surface 2. Sedimentary - made up of weathered remnants of other rocks, can be any age, older ones rarer than newer ones. i.e sandstone, mudstone 3. Metamorphic - result of existing rocks that have been placed under extreme heat or pressure: resulting rock usually quite different than what started with - i.e. marbles
Auchenorryncha
Auchenorryncha Cicadoidea: Cicadellidae Tree-Hoppers • Adults and nymphs feed on young eucalypt stems • Tended by ants • Can't jump, run around stem to avoid predators
Lecture: Australian Rivers and their Biota
Australia - Driest inhabited continent - Low average rainfall - Isolated or patchy rainfall - High evaporation rates - Little snow - Flat, thus few and shallow river channels and low rainfall - makes australia a lovely place for barely any rivers. • Riverbank (= riparian) vegetation, • Aquatic plants and animals • Transitory/ migratory wildlife • Human settlements and agriculture • Plants and animals on flood plains • Soil microbes, etc.
Australia as an ancient continent
Being an 'old continent', most of Australia is geologically very stable - Mountain building processes and volcanism no longer occur - The landscape and its soils are no longer rejuvenated by fresh rocks - Most of the 'action' now takes place in New Guinea • Some Australian landscapes are over 200 million years old • Weathering has shifted from physical to chemical
Permanent Costal Rivers: Inland - general - biological consequences - human impacts - management considerations
Biological consequence • Some endemism • Some requirement for adaptation to water conditions • Genetically distinct populations between rivers • Large and small animals Human impacts • Severe • Agriculture and some settlement • Fertile flood plains • Major modification of water flow: • damming, irrigation, • some water supply Management considerations to conserve biodiversity? Environmental flows, barrier removal, habitat and riparian veg restoration, control invaders
What are some of the similarities and differences between the mound-building behavior and mount maintenance of Australian brush turkeys and malleefowl? (megapods)
Brush turkey: · Shape of mound: round top = eggs inside, flat or dip at top = eggs not inside Male will dig little holes in mound; females will dig a little deeper in holes to lay eggs · Males build and maintain mounds (1-3 mounds); continuously make mounds during breeding season · Females must copulate w/ male to lay in his mound; males will copulate with different females · Maintenance: males defend mound against other males, females do a "stampy dance" to bury eggs, after dance males will finish burying, males do NOT really take leaves on and off (diff from malleefowl!) Malleefowl: · Only megapode to inhabit arid zone · Northern Australia Location Males make mounds & are monogamous Females lay 30 eggs a year Dig out old mounds, fill with litter, once it rains they swirl it all up to decompose it and then lay eggs into them. Fill it with sand for solar heat. Flattens out mound in middle of day and re-piles it in afternoon Chick is completely independent after hatching. Male will take stuff on and off mound to regulate temperature or eggs
FWF Invasive Species
Carp (Cyprinus carpio) SE Asia • Dominates many water systems • Survives and outcompetes natives • Muddies waterways -> consequences Trout (Salmo trutta) European • Introduced for recreation in southern waters led to decline of several small native spp (e.g. Jollytails) • Is now the dominant FWF spp in Tasmania Mosquito fish (Gambusia spp) USA • Introduced to control mosquitoes • Widespread • Considered noxious pest Tilapia (Oreochromis spp.) African • Tropical • Tasty! • Highly territorial and aggressive • Eats native vegetation • Massive evolutionary potential
Hadley Cells + ITCZ
Caused because intense heating at equator makes air rise (less dense) upwards and move towards poles where it eventually losses its heat and falls back down - creates big spinning circles called Hadley cells - near equator where air is rising it loses ability to hold moisture and you get high rainfall - where air sinks (30 degrees north and south) you get high pressure sinking air which means clear skies and arid climates • Intertropical Convergence Zone - area near the equator where winds from the Northern and southern hemisphere converge resulting in increased precipitation - the zone changes depending on season, during Australian summer it migrates southward
Inland Flood Plains - general - biological consequences - human impacts - management considerations
Characteristics - Anastomozing channels/river beds - Long periods of drought - Extremely widespread flooding - High temperatures and evaporation rates - Shallow, turbid water - Very little structure - Water not restricted to river bed Biological consequences • Biota NOT restricted to waterways • Very little endemism, less diversity • Genetically uniform populations within flood region • Highly mobile/migratory species • Adaptations to wide range of water conditions • Opportunistic life histories Human impacts - minimal Management considerations to conserve biodiversity? Environmental flows, barrier removal, habitat and riparian veg restoration, control invaders
Lectue: Australian Insects: High Species Diversity
Contributing factors: • Small size: allows fine grained exploitation of environmental heterogeneity • Short generation times • Sophisticated sensory and motor organisation • Co-evolutionary relationships with plants and parasites • Metamorphosis • Mobile winged adults
On what basis has it been proposed that passerine birds (perching birds) originated in the Australian part of Gondwana?
DNA sequencing indicates that origin of passerines was in Gondwana *The world's oldest passerine fossil was found in Southeast Queensland → 55 million years old Very high diversity of passerine species in Australia Studies based on DNA hybridization and sequencing indicate that passerines have their origin in Gondwana ~85-90 MYA
Lacture: Australia's fresh water fishes
Describe the general characteristics of Australia's freshwater fish fauna • Describe some key conservation challenges to Australian fish species, providing examples to illustrate these concerns • Provide some detailed examples of how fish populations survive and persist in central Australian waterway
Characteristics of marsupials
Epipubic bones - Epipubic bones are a pair of bones projecting forward from the pelvic bones of modern marsupials and most non-placental fossil mammals: multituberculates, monotremes, and even basal eutherians (the ancestors of placental mammals).
What factors might have contributed to the diversity of these groups?
Factors that may have contributed to their diversity Small size: allows fine grained exploitation of environmental heterogeneity Short generation times Sophisticated sensory and motor organisation Co-evolutionary relationships with plants and parasites Metamorphosis Persist in times of environmental stress Mobile winged adults Pangaea and Gondwana Some taxa of insects are highly mobile Introduction of insects to new areas by humans
General: Australia's FW Fishes
General • Australia only has 280 species of freshwater fish • Low compared to rest of world • Due to dry, flat continent = no big lakes, few areas that are suitable for fishes • Low ability to diversify due to lack of habitat as well
What have been the impacts of red imported fire ants in Aus?
Impacts of red imported fire ants in Aus 2 invasions in Brisbane, one in Gladstone - Predate on other ants and small animals - Attack seedlings, disrupt dispersal, and decrease forests - Hurt environment by degrading biodiversity - Aggressive and noxious sting - human health hazard due to venom - Damage government infrastructure (electrical devices and motors; undermine paving and roads) - Negative effects on tourism (decreased use/enjoyment of recreational areas) - Hurts agricultural industry: direct damage to plants, attack farm animals (calf eyes) (effect: Environment, health, gov infrastructure, agricultural, and social anemity/tourism - decreased enjoyment of outdoors areas)
Australia's general geology: rocks in different areas
In general, Australia gets progressively younger from west to east • Rocks in Western Australia are over 2,500 million years old • Rocks in central Australia range from 600 - 2,000 million years old • Rocks in eastern Australia are younger than about 600 million years old • New Guinea began to form around 20 million years ago and is still 'growing'
Diprotodontia
Kangaroos and Wallabys - • Macropodoids include grazers (grass- eaters) and browsers (leave eaters) - Dentition similar to hoofed placentals • Able to digest cellulose in the stomach - Stomach divided into chambers similar to those of ruminants (cows and sheep) - Has allowed macropodoids to diversify with the spread of grasslands as the continent has become more arid • Defense depends on fast locomotion - Convergent on hoofed placentals (horses and cloven-hoofed mammals) - Mode of locomotion (hopping) is very different • Convergence does not need to involve only morphological similarity.
2 major topographic features of Eastern Australia
Main Divide ('Great Dividing Range') - 'High' ground along eastern margin - Divides major river catchments - Subdued topography An escarpment that runs from cairns to southern victoria • Great Escarpment - Usually to the east of the Main Divide - May have resulted from rifting between Australia & New Zealand
What are some of the main threats to various types of Australian parrots and how do these relate to aspects of their feeding and reproductive behavior?
Main Threats to Parrots Forest / Bushland Parrots Loss of habitat from land clearing = no food / no house Ground nesting parrots Have greatest decline from introduced predators (cats / foxes) Altering habits (night parrot hides in spinifex) More danger / no predictable attacks Tree Hollow and nesting species Logging of old trees with holes lead to less nesting sites for parrots • Forest & bushland dwelling species - General loss of habitat due to land clearing. - e.g. orange-bellied parrot (Neophema chrysogaster) — migrates across Bass Strait, breeding in Tasmania in summer, over-winters in southern Victoria. Habitat loss in both areas • Ground nesting species - Have experienced the greatest declines, mainly from introduced predators (particularly cats and foxes) - e.g., night parrot (Pezoporus occidentalis) - arid central regions, but might persist due its habit of hiding in dense spinafex • Tree hollow nesting species - Selective logging of old trees and clearing of old trees that contain tree hollows - leading to shortage of nesting sites. - e.g., Carnaby's black-cockatoo (Calyptorhynchus latirostris) Eucalypt wood lands of south-western Western Australia
Naming of bird species by Europeans
Many species of Australian birds were first named by early colonial settlers from England • Based on their resemblance to bird species from Europe, Australian birds were given equivalent common names (e.g., 'robins', 'magpies', 'honey-eaters' etc)
Monotremes are mammals because: Monotremes are unlike mammals because: Monotremes differ from marsupial and placental mammals because ...
Monotremes are mammals because: They have fur and suckle their young on milk They are endothermic (able to produce their own body heat) Monotremes are unlike mammals because: They lay eggs, so the young hatch Monotreme = "one hole" cloaca for excretory and reproductive systems Different mode of reproduction (lay eggs) Lower metabolic rate (30% placental mammal of same size) Lower body temperature (~32 c.f. 35-380C)
What are the five most diverse groups of insects in Australia?
Most 5 diverse groups of insects in Australia Hemiptera (bugs) Diptera (flies) Coleoptera (beetles) Lepidoptera (moths and butterflies) Hymenoptera (ants, bees, wasps, sawflies, and wood wasps)
Australia's murid radiation
Murid rodents (rats and mice) are generalists, and live almost anywhere and eat almost anything - Ideal'colonists' • Murids rodents are granivores (seed-eaters) - Robust dentition that can deal with just about anything • Granivores are conspicuously absent among marsupials (fossil and living) - The absence of granivores in Meganesia when the first murids arrived 5 million years ago meant they were able to radiate into almost every conceivable rodent niche, including many occupied by non-murid rodents elsewhere
Describe the similarities and differences in anatomy, lifestyle and general biology between the different Australian monotremes.
Of the still living monotremes there is one terrestrial lineage (echidna) and one aquatic (platypus) Look radically different from outside because of niches they occupy but there is a lot of features that unify them and make them monotremes Monotremes retain a lot of primitive feature: cloacal - one opening in and out Burrow Platypus burrow: in river bank above flood zone Echidna: base of hollow trees, or may use burrows of other animals (monotremes) Electricity Both can detect electricity to detect prey Platypus dives can't see at all and relies on detected electricity Their bills are very sensitive. Echidna uses to sense termite mound sticks nose in) if mound is a live it will expend energy to dig out Platy will use to catch prey Venom Platypus has functional venom systems while echidna's venom systems are degenerated from lack of use Habitat and prey Platypuses are aquatic and prey on aquatic food such as anthropods and fishes. Echidnas are terrestrial and prey on termites etc.
The three major groups of parrots
Parrots, Lorikeets and Cockatoos
Lecture: Au bird diversity Passerines and Non-Passerines
Passerines ('perching birds') — 42% of species - ~310 species belonging to ~35 families - Most are small, the exceptions being crows, lyrebirds etc. - Three toes directed forwards, free of webbing, and one toe directed backwards, joining the foot at the same level as the front toes. - None swim or make a living on salt or freshwater - 'small bush birds' or SBJ's ('small brown jobs') • Non-passerines (everything else) — 58% of species - ~ 450 species - Include ratites, penguins, birds of prey, cuckoos, seabirds, mound-building birds, parrots, kingfishers, ducks and geese, rails, cranes, ibis, quail etc. - Lots of toe combinations - Lots of lifestyles and large range of sizes
Sternorrhyncha
Psylloidea aphids and things • Australian Psylloidea >10% of world fauna • 85% of described species on Myrtaceae, 90% on Eucalyptus • Lerp forming Spondyliaspinae
*what is coopartive breeding?
Rare (6% of all avian species): Cooperative breeding, when more than two adult birds help to raise a brood of young - usually facultative Usually dominant breeding male and female helped by others to feed chicks and defend territory Helpers are often related to parents, i.e. offspring from previous breeding or siblings — can be explained by kin selection when offspring receive care from more than 2 adult birds; usually facultative (not dependent) dominant breeding male+female are helped by others to feed chicks & defend territory "helpers" are usually offspring from previous breeding/siblings Can be unrelated genetically!
My notes RIFA
Red Introduced Fire Ants • Has spread across world • In area of origin not a huge problem, but where it has spread it is a big issue • Nuisance in urban areas - form very painful blisters, don't just bite but sting and inject venom • Destroy lateracle substations • Potential pest of agriculture in Au, already pest in US. - can blind calfs by biting eyes • Can cause direct damage by feeding on crops • Will attack small vertabrates, chicks etc. • Terrible threat to conservation and have economic impacts as well • Workers feed queen by regurgitating their own food so cant destroy colony by trying to posion queen because she only eats what the worker ants have already eaten - why can feed posion that doesn't kill right away? • Some ants can fly upto 5 K = large range for ants to make new homes
Compare and contrast reproduction in monotremes and marsupials
Retain reptilian style amniotic egg as opposed to egg fertilized inside as in marsupials and mammals Uterus different shapes Very small eggs in monotremes = lots of development occurs external to egg (babies suckle) = helplessness - covergent between birds and males - care for young Birthing process a lot easier because of this Marsupial has dysfunctional right ovary - not sure why Monotremes: lay eggs and have very low metabolic rate relative to placental mammals - about 30% of placental mammals = because they have much lower body temperature If in water that is 28 degrees only have to raise 4 degrees rather than 10 degrees Eggs hatch at Australian summer - huge maternal cost to generate milk = mother must eat a lot.
What evolutionary scenarios are currently used to explain the presence of the various groups of passerines that occur in Australia today?
The splitting of Gondwana into pieces is what drove the evolution of the three suborders. The order is New Zealand broke off from Gondwana roughly 82-85mya, which caused the evolution of New Zealand Wrens (some flightless) → cannot fly to Aus New Zealand wrens originated ~82- 85 MYA, just after NZ started to break away from Antarctica (* final separation of Zealandia from Gondwana is ~50 MYA) None of these actually made it to Australia Suboscines then evolved with the splitting off of Western Gondwana (does not include Australia) ~80mya Only 1 species has made it back to Australia through southeast asia 'Suboscines' evolved in western Gondwana (Africa/ India/ South America) ~80 MYA Song Birds evolved with the splitting of Eastern Gondwana 58~60mya, but took several million years for them to diversify Oscines' or 'song birds' originated in eastern Gondwana at least 58-60 MYA, diversified in Australia ~35-40 MYA
The thermal equator
The thermal equator (also known as "the heat equator") is a belt encircling the Earth, defined by the set of locations having the highest mean annual temperature at each longitude around the globe. - The thermal equator moves from north to south with the seasons because of the tilt on the Earth's axis • The centre of the High Pressure Cells also changes latitude with the seasons • Summer - High Pressure Cells move toward the South Pole • Winter - High Pressure Cells move towards the Equator
Discuss the functional role of platypus venom
Three roles of venom Predation (snakes), defence (stingrays), competitor deterrence - male to male combat during breeding season - platypus. Platypus actively uses but echidna doesn't use anymore Platypus males painfully sting each other with venom Females don't develop venom glands - only become engorged in sexually mature males during breeding season and then venom cells shrink again after breeding season
Crazy Ants Christmas Island Feed Back loops Understory
Understory CA invasion = crab predation = reduced herbivory on forest floor = plant density and diversity increase = rainforest understory dramatically changed
Characteristics of tramp ants
Unicoloniality: workers can move between nests Low levels of intra-specific aggression Polygyny: many queens per nest Generalized nesting habits: often in "disturbed" areas Broad diets Well developed mutualisms with honeydew-secreting Hemiptera
Discuss body temperature in monotremes - how are they different from other mammals? how do they differ between species of monotremes?
Warm bloodedness - monotremes have cooler blood than other mammals Monotremes have much lower body temp = reduces the amount of energy they have to take in Foraging time at day - a lot of resting Unlike mammals - if we vary our body temp a few degrees, we will have extreme metabolic issues (acutely sensitive to temp fluctuations) In monotremes they are able to tolerate much greater changes in temperature (very characteristic of reptiles) Able to maintain body temp during egg incubation. Differences in patterns in body temperature reasons: Incubation, hibernation-like states (torpor- can do in one day) - body temperature cools and they just kind of slow down Can also do true hibernation (weeks - months)
Monotremes: Western long-beaked echidna
Western long-beaked echidna - 1/4 extant species - Aboriginal rock art illustration depicting the long-beaked echidna, which researchers believe may have survived in WA's remote Kimberley region longer than previously thought based on a specimen (left) found in the Natural History Museum (London) collected from WA in 1901. 5 living species across sahul
What is being done to try and manage RIFAs in South East Queensland.
What is being done to try and manage RIFAs in SE Queensland? Education on the public Locating nests and injecting insecticides Hard to eradicate because high reproductive rate, cover huge areas, whole colonies can relocate themselves
Sternorrhyncha Coccoidea - what is it - what happened - 3 outcomes
World wide pest Cottony cushion scale pest of citrus in California: beginning of modern biological control - lmost destroyed citrus groves industry in Cali. - Later released into Australia and it was not a pest here - People searched Australia for predator to pest and introduced 2 insects into Cali as predators Three outcomes 1923: University of California formally charged with biological research responsibility, led to rapid expansion in biological control research. • Early 1900s "Ladybird madness": due to limited understanding of the ecological interactions entomologists collected and released many different species of ladybirds (40 species from Oceania released, only 4 even established). [it was fortuitous that Rodolia sp are specialists on magarodid scale insects]. • 2002-2006: R. cardinalis released to control I. purchasi infesting endangered species in Galapagos.
All 3 groups of mammals...
co-existed in Australia before it separated from Antarctica 42-38 mya
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3 groups of mammals in AU
monotremes (2% of Au. *native* Monotterrestrial mammal fauna) marsupials (73% terrestrial mammal fauna) eutherians (25% - include bats, rats and, depending on opinion, the dingo, non-native = opossum)
RIFA management in Southeast Queensland: eradication programme + Obstacles to irradiation Has program worked?
• $250 million spent since 2001 • Public awareness campaign • Programme based on locating nests (public reports) • Nest then injected with insecticide • Local search for more nests • Area in locality of nest treated with bait (IGR) Obstacles to eradication • Large area infested: impossible to treat all of it • RIFABiology/ecology: • High reproductive rate and ready dispersal • 1000s of reproductives/ colony • Mated females establish colonies wherever they land • Queenscanfly1-5km • Whole colonies can move • Polygynecoloniescansplitintomanynewcolonies • Queensprotectedfrompoisonsbycolonyfeedingsystem • Has this worked? • 65,000 nest found in 2001; 600 found in 2009
An archipelago of volcanoes
• A chain of relatively recent volcanoes extends down the east coast of Australia, centred on the Main Divide • Probably related to volcanic activity over a series of active hot spot (similar to the one under the Hawaiian Islands today) • Near Brisbane - Melany volcano (25 mya) • Glass House Mountains - Main Range volcano (24 mya) - Focal Peak volcano (24 mya) • Mt Barney - Tweed volcano (22 mya) • Lamington NP - Bunya Mountains volcano
Conclusions and practice questions
• Australia has the most variable water supply of any inhabited continent • Aquatic habitats and populations are patchy in space and time • Documentation of the diversity of aquatic habitats in Australia is woefully incomplete, especially for inland water systems • Humans need water too = vulnerable and of high management concern Q1. If you were to manage an inland permanent river system to preserve aquatic biodiversity, what characteristics would you attempt to maintain? Explain why. Q2. Describe three major characteristics of biota that inhabit water systems similar to Qld's channel country (Inland Flood Plains).
Southern High Pressure Belt and Aridity
• Australia sits between 10-45o S • Directly under the influence of the southerly High Pressure Belt • Lots of warm, dry, descending air conferred on the continent by easterly moving anticyclones • Few clouds, hot, low rainfall
Freshwater flow in Australia vs. US
• Australia's largest river has a 1cm flow rate, in Europe highest is 20, in U.S. it is 40 • Most rivers don't flow most of the time
Australian Lung Fish
• Australian Lungfish Neoceratodus forsteri • Found naturally in the Burnett R and Mary R • Living fossil - obtains O2 from water via gills and from air via a single, simple lung • Survives 2 hrs - 2 days (if moist) out of water, • Only breathes air when in hypoxic water (breath ea 30-60 min) • Australia has one of six species in the world • This species have one lung = if they keep their gills moist they can survive for up to two days out of the water - not easy • Allows them to supplement their oxygen intake • Need flowing water, specific vegetation - human impacts effect a lot because they're picky and will not breed unless conditions are right • There was proposal to dam Mary river, lungfish stopped this proposal because it would likely wipe them out. • Lungfish only live in 2 rivers - mary and brun •Cannot survive in dried ponds unlike African/ S. Am. spp. • Long lived, 40-100 y, adults at 15 y • Shelter in complex habitat • Rely on shallow, vegetated pools to breed and feed, and cover for juveniles • Spawn annually
General info Australia's climate
• Australian climate is strongly influenced by its high insolation (amount of solar radiation hitting the surface) - Australia sits within an 'anticyclone' or High Pressure Belt • Lots of descending, warm, dry air • Little cloud cover • Solar radiation (and evaporation) is high • Australia's flat topography means that there are few strong barriers to intercept rain from moist maritime air • Australian climate is under the influence of major global southern circulation patterns of the ocean and atmosphere
Conclusions and sample exam Q's FWF
• Australian freshwater fish species are: • Relatively few • Their composition differs markedly from other continents • Largely endemic with unique characteristics • Doomed? • Australian freshwater fish are vulnerable to a variety of threats including: • Barriers to migration within rivers or between rivers and the sea • Loss of environmental flows • Destruction, modification and loss of habitat • Introduction of exotic species • Recreational fishing Q. Describe one example of how an Australia fish species is able to survive in Australia's desert waterways. Your answer should include both how the species survives from one generation to the next and how an individual survives during its lifetime. Q. The river that is home to the Qld lungfish was to have a dam built on it. Describe three ways in which this would have potentially impacted upon the survival of lung fish populations. Justify your answer.
Summary
• Australian insect fauna is highly endemic • Extensive radiations on Myrtaceae and Mimosaceae • Fauna poorly studied; particularly when compared to flora and vertebrate groups • Australian arthropod fauna estimated to be 253,000 species; of these 205,000 are insects- thus, at least 75% of insect fauna is not described or yet discovered
Challenges facing FWFs
• Barriers to movement • Lack of environmental flows • Habitat modification • Invasive species
Australia's Extant Fauna
• Be familiar with the fossil heritage of Australia's extant mammal fauna • Known the main groups of mammals that exist in Australia today - Monotremes - Marsupials - Bats - Rodents
Desert Gobi
• Bottom dweller - has no swim bladder • Found in artesian springs and salt lakes • Grow fast, rarely live for more than one year • Lay eggs under rocks; males protect eggs • Tolerate 5-41oC , FW to twice concentration of seawater, wide range of pH (6.8 - 11.0) • During high temps it lies in the cooler silt on the bottom • Low O2 in water as the pool dries out fish lie with front of body out of water so gills can obtain O2 from the air. They do this by buccal (mouth) pumping.
Australian outback - nutrients - types of common soils compared to other continents
• Chemical weathering tends to leach out rarer minerals that are essential for life • Phosphorous is typically very low in Australian soils (10-400 ppm compared to >500 ppm in most other continents) • Nitrogen is also a limiting factor • Sands, texture contrast soils and clays are more common than on other continents • Saline, sodic, low nutrient and hard setting soils are very common - • Leaves iron and aluminum oxides concentrates = why lots of Australia landscapes are red
2 Important FWF species
• Cod - most Speciose family in Australia • Jollytails - are also common - Australia and NZ have most of the world's species
Intermittent Rivers: My notes
• Don't flow all the time naturally • Dry most of the time but along them end up with series of disconnected little billabongs or waterholes • Areas that persist are the billabongs - quite deep but have no flow = little oxygen • End up with genetic similarity because not much chance for migration • Flooding allows for moving between billabongs and reproduction etc. • A lot of the species don't live in rivers but take advantages of rivers when they're there
Salt Lakes and Clay pans - general - biological consequences - human impacts - management considerations
• End of the road • Salt from soils • Extremes in salinity • Shallow waters with extremes in • temperature • oxygen • water supply Biological consequences • Biota widespread ('raining fish') • Low species diversity • Massive extremes in population size • Genetically uniform populations • Highly mobile/migratory species • Tolerance to multiple extreme water conditions e.g. hardyhead—opportunistic life histories, very fast life cycles Human Impacts - almost none - no modification to water flow Env. Considerations - Environmental flows, barrier removal, habitat and riparian veg restoration, control invaders
Auchenorryncha and Eucalyptus
• Eucalypts shed bark annually • Leafhopper (Ledrinae) flattened to exploit this habitat • Eucalypt leaves hang vertically to reduce impact of midday sun • Khaono montana produces silk shelters to reduce water loss
Lecture: Geology and Landforms of Australia Read and see aims
• Geologyandclimatearetwoofthemajor abiotic components of Australia's terrestrial environment • Geologyandclimatemustbeunderstoodin order to understand ecology—they are fundamental factors influencing biota - Geology influences soil, which influences what plants can grow, which in turn influence the distributions of certain animals - Significant landforms can affect climate and the distribution of some biota Aims Teach you some of the fundamentals of Australian geology and landscapes, both of which have implications for vegetation and ecology • Highlight some of the major landforms that you may encounter on field trips and which also have an affect on rainfall At the end of this lecture you should know.. • That Australia is an 'old continent' - What this means and its ecological implications • Basic rock types that occur in Australia and their relative nutrient levels • Some key Australian soil types • About the broad topography of Australia, including the Main Divide, Great Escarpment, Lake Eyre Basin, Great Artesian Basin and the Murray-Darling River system
Australia's weekly weather
• High Pressure Cells and Polar Fronts move from west to east because of the Earth's rotation • Australia's High Pressure Cells tend to 'bud off' more or less stationary cells in the Indian Ocean • Weather at mid-latitudes is an almost continual progression of Polar Fronts
Christmas Island: Yellow Crazy Ant invasion
• Huge red crag migration • They live in the forest and every year go to sea to spawn then return to forest • In 1930's yellow crazy ant invaded Christmas island - comes from Africa • They attack crabs in numbers and prey on them • Graph - looked at activity of crazy ants where they had invaded and areas where they haven't invaded and crabs dead in invaded and uninvaded areas as well as little (crabs eat from forest floor) in invaded and uninvaded areas • In invaded areas there is much more of a build up of organic material because crabs aren't there to eat as much = invasive weeds move in because crabs aren't there to clean up exotic seedlings • Canopy dieback for 2 reasons • Crazy ants come in, prey on crabs, reduce herbivory on floor, weeds take over, • Establish, scale insects proliferate and ** see slides that show feedback loops
Bull Shark
• Includes Brisbane River, 50 km upstream • Most common attacks (6 attacks in 1990s) rarely lethal (taste and spit) - just bloody painful • Travel from seawater to freshwater • Juvenile stage in FW (avoid predators, competitors, parasites and abundant food) •One of few sharks that can live in fresh and salt water
Lecture Weather and Climate : See aims + weather vs. climate
• Know some of the fundamentals of Australian climate and weather, and the way that these influences terrestrial ecosystems • Understand how El Nino Southern Oscillation works and its implications for Australian climate patterns • Weather - Day to day physical properties of the troposphere (inner layer of the atmosphere containing most of the earth's air) • Temperature, pressure, humidity, precipitation, sunshine, cloud cover, wind direction and speed etc • Climate - The average, long-term weather of a particular area, including seasonal variations
el nino/la nina + southern ossilation
• La Niña conditions - The Humboldt current brings cold water northwards along the west coast of My notes El Nino Southern Oscillation • Measured with 'southern oscillation index (SOI)' = difference between mean sea surface pressure at the center of the pacific and the western side of the pacific • La Nina - when we have strong trade winds that force cold water (from west coast of south America across pacific towards thermal equator) - cold water upwelling on south American coast, Eastern pacific and warm water on western pacific • El Nino - trade winds weaken or might not blow at all or blow in reverse direction • Consequence is all the cold watr around south America does not get pushed across = the whole pacific gets warmer and a lot of precipitation in center of pacific rather than at Australian part of pacific
cockatoos
• Large parrots with moveable crests • Don't tend to have as brightly coloured plumage as other parrots • Most eat seeds; have robust bills • 12 species in Australia; cockatoos appear to have originated in Australia • Require large nesting hollows because of their large size
Desert Fish Fauna
• Low diversity - 33 species from only 11 families - Uniform distribution in each water system (e.g., most waterholes contain 80-100% total species for that system - Wide environmental tolerances temperature: most tolerate 7-37°C - Salinity: all survive transfer to 50% SW, some to 100% - Hypoxia: most tolerate low O2 (few data) - Reproduction linked to flooding in most species - Only 3 exotic species present - Many endemics between water systems
Lungfish Breeding
• Males travel to breed - restricted by natural and man-made barriers • Resorb eggs or milt if spawning habitat is disturbed • Hatched larvae are poor swimmers • Conservation status = vulnerable • These rivers subject to damming • Reluctant to seek new breeding grounds
The life history of feeding and breeding of parrot groups
• Many species are long-lived (50+ years) • Most parrots are monogamous and pair for life • In some species both parents share incubation, in others only the female incubates. In some of these she is fed by the male. • Usually both parents feed nestlings and fledglings. • Most parrots need hollows in trees for nesting- relatively safe but often in short supply - some species are ground nesters.
Marsupial characteristics that distinguish from placentals
• Most of the characteristics that distinguish marsupials from placentals are reproductive or embryological. - A major characteristic of marsupials is that they produce very small young after a short pregnancy • Other key characteristics of marsupials - Pouch - Number and morphology of teeth differ to placentals - Presence of an epipubic bone in both sexes (absent in placentals) - Specialised ankle and foot morphology
lorikeets
• Mostly inhabit forests and woodlands • Mainly eat nectar, pollen and flowers, especially of eucalypts, banksias, melaleucas and grevilleas; get sugars from nectar and protein from pollen - have brushes on ends of tongues for lapping up nectar • Have longer, thinner bill than other parrots • Flowers are an ephemeral resource, so lorikeets tend to wander widely in search of food • Apparently garish colours are good camouflage in leaves • Occur only in Sahul; 6 species in Australia Rainbow lorikeet Scaly-breasted lorikeet
Intermittent Rivers: Inland - general - biological consequences - human impacts - management considerations
• Mostly restricted to defined river beds • String of permanent water holes or billabongs - periodically connected • Deeper water, very slow flow • Shaded, cooler temperatures • Often low oxygen levels (hypoxia) • Periodic widespread flooding Biological Consequences • Genetic similarity within river catchment (populations mix during widespread flood) • Adaptations to prolonged low oxygen • Ability to regulate reproductive output • Species mobile during floods • Less endemism • Large trees only as permanent vegetation Human Impacts • Grazing agriculture, • Few settlements Management considerations to conserve biodiversity? Environmental flows, barrier removal, habitat and riparian veg restoration, control invaders
Spangled Perch
• Present every type of aquatic habitat in Central Australia. • Tolerate 4-42oC • Possibly aestivate, either as eggs or adults, but no evidence. • Exceptionally good dispersal abilities e.g., Shipway (1947) records hundreds of young spangled perch swimming 16.6km (10 mi) in 6 hrs along a wheel rut until the water seeped away. • Flooding is not needed to stimulate breeding • Need temps >26oC to lay eggs - large numbers of eggs • They can occur in extremely high abundances...
The distinguishing characteristics of parrots and megapod birds
• Short, deep, downward pointing bill • Two toes pointing forward and two pointing backwards (also seen in cuckoos and some kingfishers) - most seeds or nectar, some also eat fruit, insects, - beak to crack open - tongue very important to feeding - lorikets have brush on end of tongue
Dingo
• Sub-species of the grey wolf (as is the domestic dog) or a distinct species? - SE Asian version (breed) of the domestic dog (Canis lupis familiaris)? - Different enough to warrant species status (Canis dingo)? • Found throughout SE Asia - Large populations in Thailand, Sumatra, New Guinea (NG singing dog) • Oldest dingo remains in Aust. come from Madura Cave on the Nullarbor - 3,500 BP • Introduced to Australia by seafarers from South East Asia • Native or feral?
Trade Winds
• Surface air moving back towards the equatorial trough formed by Hadley Cells - used for sailing across oceans - Move predominately SE in the Southern Hemisphere - Move predominately NE in the Northern Hemisphere • Over water, Trade winds quickly gain moisture • Over land, Trade winds descend as warm, dry air
The essence of Australian Weather
• The continent lies directly under the influence of the southern High Pressure Belt • Low and highly erratic (unpredictable) rainfall • Strongly affected by the El Niño-La Niña phenomenon
Rodents - 3 waves
• The first wave of murids invaded Australia from SE Asia via the Indonesian Archipelago about 5 million years ago - 'Old endemics' - 60 species - Zygomys, Pseudomys, Melomys, Mesembriomys • The second wave of murids invaded from SE Asia via New Guinea about 2 million years ago - 'New endemics' - 8 species - Hydromys, Rattus spp. • A third wave arrived with Europeans, 200-300 years ago - Brown rat (Rattus norvegicus) - Black rat (Rattus rattus) - House mouse (Mus musculus)
Polar Fronts
• The formation of 'fronts' is a significant climatic process that occurs between High Pressure Cells and the Poles • Polar regions - produce cold, relatively dry air • Large bodies of cold, dense air spiral around Antarctica in the Southern Ocean • This cold air will push warmer, moister oceanic air upwards, causing rain - These zones of pressure interaction are called polar fronts
Marsupial Meat eaters
• There is a conspicuous lack of medium to large marsupial carnivores in Australia • Only 5 convergent niches have been occupied by marsupial carnivores - Bear-like omnivore Propleopus (giant rat kangaroo, some diprotondontoids - extinct) and Nimbadon (an extinct tree-climbin diprotondontoids) - Scavenger Sacrophilus (Tasmanian devil) - Large cat-like Thylacoleo (marsupial lion - extinct) - Dog-like Thylacinus (Thylacine - extinct) - Civit/small cat-like Dasyurus (quoll) • Not due to any constraint linked to being a marsupial - The fossil marsupials of South American include a large diversity of medium to large carnivores • The low nutrient content of Australian soils may have restricted the diversity of peak consumers (the carnivores) • Alternatively, the low diversity of marsupial carnivores may be an artifact of a patchy fossil record
The Great Artesian Basin
• Underlies about 1/5 of Australia • Permeable sandstone aquifers capped by impermeable siltstones and mudstones • Water can enter aquifers from high- rainfall areas along the Main Divide • Artesian bores provide a major water source in arid areas to allow agriculture
Soil definition and soil horizons
• What is soil? - Residual layer that develops on bedrock and/or unconsolidated sediment through physio-chemical and biological processes (pedogenesis) 'O' horizon - Surface layer of organic matter • 'A' horizon (topsoil) - Typically dark, nutrient-rich layer composed of humus, clays and other organically- derived minerals, • 'B' horizon (subsoil) - Typically paler, courser- grained layer, rich in minerals precipitated out from ground water leaching • 'C' horizon (regolith) - Layer of broken bedrock
Australian Rivers and Fish Kills
• millions of fish dying because no oxygen in river because of too much water being extracted further upstream mainly for cotton
Permanent Costal Rivers: Coastal - general - biological consequences - human impacts - management considerations
• some have endemic species to the rivers • southern Au doesn't have very large vertebrates • northern has crocs, bull sharks • human impacts usually sever because humans like to inhabit them - constant water, clear well oxygenated fast water Biological consequences • Biota restricted to waterways • Some degree of endemism • No requirement for water-related adaptations • Genetically distinct populations between rivers • Usually small animals • Many different species Human impacts • Moderate to severe - settlement and agriculture • Modification of water flow for water supply, irrigation, hydro-electric power Management considerations to conserve biodiversity? Mary River, Qld Environmental flows, barrier removal, habitat and riparian veg restoration, control invaders
