Diseases outbreaks associated with high population on the Island discourages immigration of organisms to the Island Natural calamities such as earthquake, fire, floods may also discourage immigration of organism to the Island. The rate of extinction of organism on Islands increase exponentially with increase with the number of species on the island. Environment resistance in form of diseases reduces the number of organisms on the island. The producing population on the island may be so small that the chances of finding a mate is very low. This makes the organism to dies before producing young ones leading to extinction. The number of predators increase on the island eat the prey to extinction. Natural calamities such as flood may cause massive death of organism leading to their extinction. Competition for resources such as food, shelter and mates increase as the population increases. The better adapted species survive while the less adapted die or escape from the island and eventually become extinct. From figure 1, 2, 3 what conclusions can you draw what determines the number of species on an island? (05marks) Size of the island Distance of the island from the shore Number of species on the island Rate of immigration to the island Rate of extinction of organism from the island Describe how factors other than those depicted in information provided, may affect the immigration of new species on an island. (4marks) Resource availability; if an island has a large resource base, more species are attracted to it. However, the number of immigrants eventually reduce the resource on the island leading to extinction of species. Predation: presence of predators on the island discourage immigration of the prey organism, presence of the prey encourages immigration of the predator. Species mobility; species that can fly or swim are able to migrate to a fur island or run away from predators and can easily search for food. Environmental conditions on the island: favorable conditions on the island encourage immigration of large number of species. Accidental introduction of new species to island, Suggest the factors that would cause immigration of new species to a virgin land. (5marks) Availability of food Availability of shelter Absence of predator
Diseases outbreaks associated with high population on the Island discourages immigration of organisms to the Island Natural calamities such as earthquake, fire, floods may also discourage immigration of organism to the Island. The rate of extinction of organism on Islands increase exponentially with increase with the number of species on the island. Environment resistance in form of diseases reduces the number of organisms on the island. The producing population on the island may be so small that the chances of finding a mate is very low. This makes the organism to dies before producing young ones leading to extinction. The number of predators increase on the island eat the prey to extinction. Natural calamities such as flood may cause massive death of organism leading to their extinction. Competition for resources such as food, shelter and mates increase as the population increases. The better adapted species survive while the less adapted die or escape from the island and eventually become extinct. From figure 1, 2, 3 what conclusions can you draw what determines the number of species on an island? (05marks) Size of the island Distance of the island from the shore Number of species on the island Rate of immigration to the island Rate of extinction of organism from the island Describe how factors other than those depicted in information provided, may affect the immigration of new species on an island. (4marks) Resource availability; if an island has a large resource base, more species are attracted to it. However, the number of immigrants eventually reduce the resource on the island leading to extinction of species. Predation: presence of predators on the island discourage immigration of the prey organism, presence of the prey encourages immigration of the predator. Species mobility; species that can fly or swim are able to migrate to a fur island or run away from predators and can easily search for food. Environmental conditions on the island: favorable conditions on the island encourage immigration of large number of species. Accidental introduction of new species to island, Suggest the factors that would cause immigration of new species to a virgin land. (5marks) Availability of food Availability of shelter Absence of predator
Ecology-questions-and-answer.docx