Prof Ruxton Flashcards
Describe stromatolites.
The oldest fossils: Mounds of sediment and Cyanobacteria which grew and multiplied over a huge amount of time.
Give 3 examples of triggers for dramatic change on Earth.
Extra-terrestrial collisions, volcanic activity and life-induced changes.
What was the life-induced change during the Cambrian explosion.
High oxygen levels allowed much more life to appear.
True/False: Evolution = Progress
False!
What is radiant flux density?
The rate of energy passing through unit area perpendicular to the beam.
Give 4 causes of lost sun energy.
UV absorption by the ozone, IR absorption by greenhouse gasses, scattering and cloud reflection.
How much radiation from the sun is photosynthetically active?
50%
What is the maximum efficiency of photosynthesis?
12.5%
What is the usual efficiency of photosynthesis?
1% - 3%
Why is so essential for there to be so much water in soil for plants?
They must lose huge amounts of water to gain even small amounts of CO2.
Which type of waters are most productive?
Temporate
Why have lions not evolved to be faster?
Because they have evolved to be effective ambush predators.
What is an honest way for zebras to signal detection of a predator?
Using alert posture.
What is a way for zebras to signal detection of a predator that can be fake?
Foot stamping.
Why do vultures eat cheetah poo?
Cheetahs have a very ineffective metabolism meaning they don’t get all the nutritional or calorific value for their food.
What are the costs of cheetahs being so fast?
Small prey only, half of food stolen abc inefficient digestion.
How do leopards avoid competition?
Nocturnal hunting and variable diet.
What makes African wild dogs such good long distance runners?
Inflexible shoulders, large heart and large lungs.
What is an advantage of African wild dogs excellent stamina?
They are able to exhaust large prey.
Give 3 advantages of hyenas’ powerful jaws.
Large prey can be disable with one bite, any carcass can be eaten and lions are scared away through fear of being bitten.
Give a reason there may be no sabre tooth cats currently.
There is a lack of giant herbivores in the current ecosystem.
Requiring water for thermoregulation, low aerobic scope and high lactate tolerance are all characteristics of what type of predator?
Ectothermic predators
What is a cost of excellent visual skills in avian predators?
Poor performance at low light levels.
