Animals Test 2 Flashcards
(23 cards)
What are some general threats to herpetofauna?
Range restriction, loss of aquatic habitats, agriculture, gen; pollution, urbanisation, cc, invasive spp. disease, overharvesting
What are some ecosystem services provided by herps.?
Regulation, Provisioning, Supporting, Cultural
Regulation ES?
Pest control, population regulation
Provisioning ES?
Medicine, food
Supporting ES?
Nutrient cycling, soil aeration
Why study mammals?
Most dominant vertebrate, Diversity, R28 Bn revenue
How are mammals diverse?
Locomotive diversity, Morphological diversity, Habitat diversity
Habitat diversity of mammals?
Terranean - Many
Subterranean - G. mole
Arboreal - Apes
Aerial - bats
Semi aq. - otters
Mostly aq. - E. seal
Aquatic(cetaceans) - whale
Benefits of endothermy
- High, stable Tb
- Activity ind. of Tair
- Inhabit extremes
- Greater & more sustained activity
Costs of endothermy
- More energy input (high metabolic rate)
Unique mammal features?
Mammary glands, Epidermal glands, Pellage, 3 m. ear bones, heterodonty, big brain, Endothermy, lactation, Diaphragm
Mammal developed features?
Respiratory turbinates
-> Humidify and warm air
Increased development of secondary palate
Increased heterodonty
-> Teeth with precise occlusion
Gradual loss of temporal fenestrae
Single bony element in lower jaw
Name the unique features of birds
Eggs, feathers, beak, light skeleton, High metabolic and developmental rates
What ecosystem services do bird provide?
Cultural, supporting, Provisioning, Regulating
Explain the importance of ecotourism for birds
Bird related tourism - R2 bn, bird watchers best tourists
Bird identification metrics
- GISS
- Plumage colour
- Beak shape and size
- Leg length, colour, feathers
- Distribution
- Habitat
- Behaviour and call
What are the main hypotheses explaining bird diversity?
Evolutionary history; time to diversify
Developmental rates and body size
Improved dispersal due to flight
Niche exploitation
What are the adaptations for flight?
Feathers
Hollow bones & muscle structure
Size
Lay eggs
Metabolic and developmental rates
Modified jaws (beaks)
Autophagy
Specialised lungs
Explain precocial vs altricial development
- Precocial; Hatches covered in down feathers, leaves nest soon after hatching
- Altricial; Hatches naked, blind and helpless
What ecological services do birds provide?
- Seed dispersal (e.g., frugivores)
- Pest control (e.g., insectivores)
- Pollination (e.g., hummingbirds)
- Scavenging (e.g., vultures)
- Nutrient cycling
- Cultural services (birdwatching, symbolism)
What hypotheses/explanations are there for bird diversity?
- Ecological release: extinction opened niches
- Key innovations: feathers, flight, efficient lungs
- Co-evolution with flowering plants: new diets
- Geographic isolation: speciation from islands/continental shifts
What is the significance of the Latitudinal Diversity Gradient? (LDG)
- Tropics have highest bird diversity due to:
- Stable climates and high productivity
- Habitat complexity (more niches)
- Long evolutionary history (less glaciation)
- Higher speciation, lower extinction
- Critical for biodiversity conservation
Explain the adaptations birds made for flight
- Feathers (lift, insulation)
- Light, rigid skeleton (hollow bones, fused bones)
- Keeled sternum (muscle attachment)
- Strong flight muscles (pectoralis, supracoracoideus)
- High metabolism, efficient lungs
- Organ reduction (e.g., no bladder)
- Behavioral adaptations (migration, courtship in air)
