Flashcards in Lecture 11- Introduction to Birds Deck (23)
Loading flashcards...
1
How old were the fossil feathers discovered in Koonwarra, Vic?
11O MYA
2
How old were the penguins & dromornithid tracks?
30 MYA
-first recognizable fossils in Australia
3
How old were the extensive fossils of wetland birds in Central Australia?
-20 MYA
-also dicovered rare pigeons, eagles, rails, megapode & passerines
4
What was the Dromornis stironi aka Giant Demon Duck of Doom?
-'Mihirung paringmal’ (giant bird)
• central Australia - 15 mya
• Flightless, weight 500+ kg, 3m tall
• related to geese
-not clear what he ate, probably not carnivorous
5
How many species of birds are there in Australia and what is their size range?
-800
-range from 8g Weebill to 45kg Emu
6
What are the four broad categories of birds in Australia?
1. Long-established non-passerines of Gondwanan origin (emus, cassowaries, parrots)
2. Australasian passerines descended from Corvid family (fairy-wrens, magpies, honeyeaters)
3. Recent colonists from Eurasia (swallows, larks, cisticolas, some raptors)
4. Introduced species (starling, blackbird, Indian mynah)
7
What evolution is in play in the similarity of Australian birds to the Northern hemisphere?
-• however, these examples illustrate convergent evolution, not relatedness • most Aust spp. are corvids,descended from ancestors of the crow family
8
What does corvid mean?
-descended from the ancestors of the crow family
9
What is convergent evolution?
-Evolution of similar features in unrelated species
-• DNA studies allow origin and evolution to be unravelled
• prove that Aust birds not derived from northern hemisphere stock - more closely related to each other than to N.H. look-alikes
10
What are the four mating strategies of birds?
• monogamy (M+F)
• polyandry (FMMM) =more males
• polygamy (MFFF) =more females
• {promiscuity (FFMM)?}=lot of males with lot of females
11
What are the five parental care types in birds?
• biparental = both parents stay
• paternal or maternal=only one parent stays
• none
• mound-builders= build mounts of rotting vegetation that warms the eggs
• cooperative= in groups
12
What are the surveying techniques for birds?
-census, monitoring
-capture and ringing
-DNA studies
13
What is the Atlas of Australian birds project?
Aim: - collect info on distribution and abundance of Australian birds - involve community
-commenced in 1998
-voluntary based
-Some conclusions:
- some supposedly migratory species are not - winter movement of birds from SW & Tasmania to NT
14
What is the Australian Bird and Bat Banding Scheme?
-commenced 1953
-• Coordinates all banding – 600 banders, 80-100k birds/yr – central database – train & license banders
• Banding permits – A class project leader – R class experienced bander – C class trainee
15
What do we learn from capture and ringing of birds?
- lifespan, movements, observations of behaviour
-international movements
16
How does life span of birds vary?
-a lot
-1-48 years
17
What are the Wader birds an their characteristics?
-Wader birds(the ones near water) - migrating species (~3 million individuals)
-March - gather on Australian shores, then fly north
-10-15,000 kilometers, lose 50% body mass
18
What do the studies using colour-rings tell us about birds?
• dispersal • pair formation • breeding success • interactions
-can tell individuals apart even from a distance do not need to disrupt them as with normal banding to read the number
19
What is the myswan.org?
-example of citizen science
-people report sightings of swans
20
What do the DNA studies tell us about birds?
• DNA fingerprinting - mating systems
• Molecular sexing of monomorphic species
- captive management - studies of sex ratios
21
How many taxa of birds are extinct and how many are threatened and why?
24 taxa extinct, 127 taxa threatened
– large birds (>500g) more likely to be threatened than secure
- smaller birds more likely to be secure than threatened
22
Where do lot of the threatened taxa nest?
26% of threatened taxa nest in hollows – large owls & parrots in particular
- 23.3% are ground-nesting
- 50 of 133 island taxa are extinct/threatened
23