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Title: population Post by: biochicka on Apr 24, 2014 1. Explain why organisms are not evenly distributed across Earth.
2. Identify four factors that might limit the population size of animals (such as a raven) that live as scavengers. Title: Re: population Post by: bio_man on Apr 24, 2014 Quote 1. Explain why organisms are not evenly distributed across Earth. Life on Earth is not evenly distributed; the patterns of distribution are largely due to abiotic factors. Most organisms obtain their energy directly or indirectly from sunlight. Every organism requires certain levels of abiotic conditions such as temperature, humidity, salinity (saltiness) and moisture. Organisms can tolerate fluctuation in these levels but only within a certain range –there is always a level that is best for the organism. It is the abiotic factors that affect the distribution of Earth’s organisms. Title: Re: population Post by: bio_man on Apr 24, 2014 2. Identify four factors that might limit the population size of animals (such as a raven) that live as scavengers. (1) Availability of water (2) Availability of food (3) Availability of living space (geographical habitat) (4) Nesting materials (e.g., availability of brush, leaves, shelter) (5) Mean Temperature (6) Temperature Variance (e.g., differences between nightly lows and daily highs) (7) Litter size (i.e., number of offspring born per pregnancy) (8) Gestation period (i.e., duration of pregnancy) (9) Age at maturity (10) Reproductive years (i.e., duration of reproductive fitness) (11) Longevity (e.g., death rate) (12) Likelihood of natural disasters (e.g., hurricanes, earthquakes, floods, droughts) |