Unit 2 Flashcards
Behavioral adaptations
something an animal does usually in response to some type of external stimulus in order to survive.
Biodiversity
the variety of life in the world or in a particular habitat or ecosystem.
Ecological tolerance
the range of abiotic conditions in which a species can survive.
Ecosystem services
Ecosystem services are the many and varied benefits to humans provided by the natural environment and from healthy ecosystems. Such ecosystems include, for example, agroecosystems, forest ecosystem, grassland ecosystems, and aquatic ecosystems.
Generalist species
Species that can live in many different types of environments, and have a varied diet
Genetic adaptations
A biological characteristic with a heritable basis that improves reproduction and/or survival and results from evolution by natural selection.
Genetic diversity
the range of different inherited traits within a species.
Habitat diversity
the range of habitats present in a region.
Indicator species
an organism whose presence, absence or abundance reflects a specific environmental condition.
Island biogeography
a field within biogeography that examines the factors that affect the species richness and diversification of isolated natural communities.
Supporting species
a species on which other species in an ecosystem largely depend, such that if it were removed the ecosystem would change drastically.
Natural climate changes
the sun’s intensity, volcanic eruptions, and changes in naturally occurring greenhouse gas concentrations.
Pioneer species
Pioneer species are hardy species that are the first to colonize barren environments or previously biodiverse steady-state ecosystems that have been disrupted, such as by wildfire
Primary succession
happens when a new patch of land is created or exposed for the first time.
Secondary succession
a previously occupied area is re-colonized following a disturbance that kills much or all of its community
Specialist species
animals that require very unique resources.
Species diversity
the number of different species present in an ecosystem and relative abundance of each of those species.
Species richness
the number of species within a defined region
How many species are estimated to exist on Earth?
10 million
Two savanna communities both contain 15 plant species. In community A, each of the 15 species is represented by 20 individuals. In community B, 10 of the species are represented by 12 individuals; the remaining 5 species are each represented by 3 individuals. Which statement best describes the two communities?
Community A has a higher species evenness.
Phylogeny is
the branching pattern of evolutionary relationships
Which of the following is used to calculate Shannon’s Index of diversity?
I. The proportion of individuals in each species
II. The total number of species
III. The number of individuals in each species
l and II only
Which evolutionary effect results in reduced genetic variation in a community?
The founder effect
Which of the following is the best example of critical habitat?
Many species of hawk rely on trees to spot prey and would be less successful at hunting if there was logging.
Ponds are preferred foraging grounds for bull frogs, and if they were developed on, the frogs would need to forage in nearby rivers, which have less available food.
Wetland and riparian ecosystems are vital foraging and breeding grounds for the endangered whooping crane.
Alaska Native American tribes sustain their communities with wild salmon, and the salmon rely on specific river habitats to repopulate.
Nomads in the Sahara have long relied on scattered oases as a source of food and water for their camel herds.
Wetland and riparian ecosystems are vital foraging and breeding grounds for the endangered whooping crane.
