Predation

EVIDENCE OF PREDATOR PREY RELATIONSHIPS IN WILD NOT RELIABLE, AS HABITAT LIMITED, AREA OF TRAVEL SMALLER, LESS REFUGE FOR PREY, ENVIRONMENT LESS DIVERSE NOT POSSIBLE TO COUNT ALL INDIVIDUALS IN NATURAL POPULATION, CAN ONLY SAMPLE AND SURVEY FOR ESTIMATIONS.

EFFECT OF PREDATOR PREY RELATIONSHIP ON POP. SIZE

• PREDATORS EAT PREY, PREY POP REDUCES
• FEWER PREY = PREDATORS IN GREATER COMPETITION WITH EACH OTHER, 
• PREDATOR POP REDUCED, SOME UNABLE TO OBTAIN ENOUGH PREY FOR SURVIVAL
• FEWER PREDATORS = FEWER PREY EATEN
• PREY POP INCREASES
• MORE PREY AVAILABLE AS FOOD, PREDATOR POP INCREASES

IN NATURAL ECOSYSTEMS. PRGANISMS EAT RANGE OF FOODS, FLUCTUATIONS IN POP SIZE THUS LESS SEVERE

PERIODIC POPULATION CRASHES ARE IMPORTANT IN EVOLUTION BECAUSE THEY CREATE A SELECTION PRESSURE WHEREBY ONLY THOSE BEST ADAPTED WILL SURVIVE TO REPRODUCE - POP THUS EVOLVES TO BE BETTER ADAPTED TO PREVAILING CONDITIONS