Week 4 (L10-11) Flashcards
What are species abundance curves and what do they show and the implications?
Graph- ranking species by abundance vs no individuals in species (backwards exponential). Shows that most species are relatively rare
Implications (of species being rare)
- most species difficult to study ecologically
–> cannot obtain density relationships
–> focus on individuals
Example of predator prey interaction and the mechanisms of interaction
Tree pythons
Tree pythons have evolutionary adapted to living in trees and their prey capture. Their environment differs from other organisms and is not supported by stable substrate. They can’t throw coil around prey immediately and therefore must have a precise strike to get prey. For prey capture, they have long, straight and slender teeth and a flexible jaw to push teeth forward. They must penetrate prey back to body coils.
Mechanism of interactions
- Different pythons dont interact with environment in same way- even if in same area
- Intricate (numerous components)
- mutual adjustment of components
- complex adaption- development, morphology, physiology, behaviour etc
Example of pollination mutualism and the mechanisms of interaction
type of cycad (macrozamia)
- pollinated by thrips and weevils - each plant is species specific (only pollinated by one specific species)
- pollinated is coordinated
- -> male + female cones at same time
- -> october/ november (species- specific differences)
- -> specific pollinator must energy (pupa in soil) at same time
- Pollination is related to thermogenesis
- -> When the cone temperature is hot enough, the thrips/ weevils come out to pollinate- if not hot enough- won’t come out - however nights must be cooler than 17C
- -> coordinates thermogenesis peaks with insect activity peaks
Mechansims
- Timing is crucial (seasonal and daily)
- Intricate
- mutual adjustment of components - species specific
- complex adaption
Example of interaction with mates
Three spined stickleback
Complex adaptions + stabilising selection
- several intermediate steps to achieve fertilisation
- each achieves nothin on own (context + sequence)
- change to a step- organism likely to succeed
- stabilising selection (Is a type of natural selection in which genetic diversity decreases and the population mean stabilizes on a particular trait value.)
What is SMRS and what are some examples of this
SMRS= specific mate recognition system
examples
Sharp nosed grass frog–> frogs+ birds sing- relates to physics of envionment
Torrent frog–> call adapted to environmental conditions
Leopard toad–> behaviour adapted to habitat: each frog calls from particular site, lay eggs on a place where water will eventually form a pool, wages rest down to escape predators.
What are the generalisations about interactions
- complex- many components
- involve various processes- biochemical, physiological, morphological, developmental, behavioural
- influenced by diverse environmental variables
- mutual adjustment of components ( species specific- e.g. python + weevils vs thrips, frogs)
What is idiosyncrasy
Each species has different patterns and may not fit the model, making studying ecology hard/ even interesting
What is environmental matching
Life of an individual (lifeline)- must match sequence of thermal conditions in a locality if organism is to succeed
Closer the match, more abundant the the species
Several variables that can affect this, high species specifity= highly specific requirements for species, a lot of factors to consider, e.g. temp, humidity,
if only one variable or sometimes species don’t fit models–> species specifiy
Each species adapted to each potential environments
6 examples of timing and its ecological consequences
Blubells seeds in europe Pea plants Tomatoes Codling Moth Adelie penguin Large mammals
Bluebellls seeds in europe
-Ripening of seeds happens early in season in relation to 2 variables (moisture + temperature)
- seeds germinate in autumn, producing small seeds just before winter,
- to do this, spring/ summer needs to be dry/ temp high for seeds to ripen (atlantic climate)
(summer/ spring- low rainfall, autumn- high)
However, there are more variables that can affect this + more life cycles
pea plants
- needs heat as a resource for germination and production- too little/ too much can have an effect
- thermal response- conditions that plants require–> sensitive to heat
- warm spring, cool summers
tomatoes
- yield affected by the amount of consecutive days above 33C and amount of time spent above 33C
- seasons vary from year to year- affects yield - variety of variables- humidity, temp, rainfall –> depends on how organisms respond
codling moth- how organisms respond to the structure of the season
- have thermal requirements–> lives in cold climate, however has to adapt to cold + get enough heat
- needs >10C for development to occur
For adaption, larvae go into diapause when days get too short and come out when days are long enough (depend on light) - the winter has to be long enough to allow growth and development (diaper system won’t work) - however, they dies in temperatures below -32C
why they are not in sub tropics- evolved in cold area
aedlie penguin
- distribution of 3 species in different locations in antarctica and are all confined to sub antarctic islands
- go to antarctica in summer, make nest out of stones
- adapted to pack ice (broken up ice)–> closely ties to environment
- moult + feed on krill which feed on algae in pack ice
- adapted to short summer
- in winter- far north of antarctica, avoiding stable zone
- store fat for migration
- early breeding, mate immediately (little mate fidelity)
- short courtship- la early, large eggs, leave shicks sooner, chick fledge when smaller
large mammals + mammoth stepe
- few mammals with gestation > 12 months (most mammals shorter)
- all large ( tapir size + bigger)- with gestation > 12 months
- global distribution of mammal species is in areas where temperatures aren’t as extreme (no snow cover, rainfall cycles)
- tropics + subtropics- long season favourable for birth + young
