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What effect has hawaii’s geographic isolation and human influence had on native bird species
Half of native bird species have gone extinct since the 1700s
Species definition
Classification of an organism whose members are able to interbreed with the ability to produce fertile offspring
Population
group of individuals that live in the same geographic area
Natural selection is based off of
-Organisms face a constant struggle to survive and reproduce
-Organisms tend to produce more offspring than can survive to maturity
-Individuals of a species vary in their attributes
True or False: Evolution will usually not occur in small populations
True
How does knowledge of evolution impact vaccines?
Bacteria reproduce at a high rate
At a faster rate than most organisms, stronger bacteria that survives passes on traits until population evolves to become immune
Pharmacists have to predict which strain will be present in the upcoming season
Vaccines to protect from this strain are created
Key takeaway: bacteria evolves and reproduces at a high rate
Conditions for variation
have to have many species (high biodiversity) in one area, allows for a variety of traits
Ecological niche
how an organism uses its habitat
What type of niche do specialists have
a narrow niche
What type of niche do generalists have
A broad niche
Specialist examples
Koalas, Polar Bears, Giraffes
Generalist examples
Tigers, deer, lions
True or False: Generalists are more likely to be endangered than Specialists
False; Specialists are more likely to be endangered because they rely on a specific source of food and location. If this food supply is threatened or survival is challenged in locations where that food is found, specialists are more likely to be endangered. For example, Panda Bears are endangered because their primary habitat is the Yangtze Basin in China, but due to infrastructure development, Panda Bears face habitat loss. However, animals like raccoons which are generalists eat whatever is available and therefore can adapt to environments altered by humans.
Random Distribution
An organism is randomly distributed throughout an area. Occurs when resources are randomly distributed. Organisms such as trees and other plants are usually randomly distributed because their seed dispersal depends on factors like wind and animals.
Uniform distribution
Organisms are spaced out in an even way across an area. This usually occurs with territorial species or when there is high competition for resources and therefore an organisms has their own space that they inhabit. For example, lions are very territorial and hunt for the resources available in their space. Some plants may have uniform distribution because their roots excrete poison in order to compete for land.
Clumped distribution
Found when species live better in proximity or when certain resources are found in certain areas. For example, desert plants may have clumped distribution around sources of water. Another example, wolves hunt in packs. For organisms that need mates to reproduce having clumped distribution makes it easier to find mates. Humans, for example, have social cohesion which is a reason for clumped distribution.
Density Dependent Factors
Factors that are affected by the density of a population
They include:
Competition (for food, water, and mates)
Size of habitat
Food and resources
Outbreaks (this is why meat like chickens are given antibiotics—they are closely packed)
Predation (more density, better predation outcomes, for example lions wait to see large groups of animals to prey instead of attacking individual organisms for better success)
Density independent factors
Factors that affect organisms regardless of population
They include
weather events (droughts, earthquakes, volcanoes, tornadoes, hurricanes)
pollution (climate change, water pollution [oil spills, fertilizer runoff, hazardous waste] any factor that causes an unwanted health effect)
Population growth formula
(birth rate-death rate)+(immigration rate-emigration rate)
Note 
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