Bio 101-Ecology

What is ecology?

the study of the relationships between living organisms

What are the five levels of ecology?

organism, population, community, ecosystem, and biosphere

What is a poplutaion

Same species in the same area

Community

Collection of differnt population in the same area

Ecosystem

A biological community interacting with its physical environment, including both living and non-living components.

What is a population size?

Total number of indiviuals in an area

Population density

The number of individuals of a species per unit area or volume.

Clumped dispersion

A pattern of population distribution where individuals are grouped together in patches or clusters, often due to resource availability or social interactions.

Uniform despersion

A pattern of population distribution where individuals are evenly spaced throughout an area, often due to competition for resources.

Random dispersion

A pattern of population distribution where individuals are spread randomly in an area, with no discernible pattern, often due to the absence of strong social interactions or resource limitations.

What kind of distribution would you expect for a solitary territorial species?

random dispersion.

What kind of distribution would you expect for a species for which social interactions are important for survival?

Clumped dispersion.

What kind of distribution would you expect when members of the same species compete for resources?

uniform dispersion.

What are the factors affecting population growth?

birth rates, death rates, immigration, emigration, and resource availability.

What does the survivorship curves show?

They illustrate the life expectancy of individuals within a population, depicting the likelihood of survival at different ages.

What are the 3 survivorship curves?

Type I, Type II, and Type III.

Type one of the survivorship curves

describes species with high survival rates in early and middle life stages, with most individuals living to old age, such as humans.

Type two of the survivorship curves

describes species with a constant mortality rate throughout their life span, meaning individuals are equally likely to die at any age, such as some birds and reptiles.

Type three of the survivorship curves

describes species with high mortality rates in early life stages, with few individuals surviving to adulthood, such as most fish and insects.

What are the two models used to explain population growth?

The exponential growth model and the logistic growth model.

The exponential growth model

describes a population that increases rapidly without any limits, resulting in a J-shaped curve when graphed.

the logistic growth model.

describes a population that grows rapidly at first but slows as it approaches carrying capacity, resulting in an S-shaped curve when graphed.

carrying capacity

the maximum population size that an environment can sustain indefinitely without degrading the habitat. (K)

What are the reasons for population cycles or boom and bust cycles?

Population cycles, or boom and bust cycles, occur due to factors such as resource availability, predation, disease, and environmental changes that influence population growth and decline.

Density-dependent factors

are factors that affect population growth in relation to the population density, such as competition, predation, and disease.

density-independent factors.

are factors that affect population growth regardless of population density, such as natural disasters, climate change, and human activities.

Ecological footprint:

tracks the use of productive surface areas.

What is the environmental impact of population growth?

Increasing the extraction of resources from the environment.

demographic transition

is the transition from high birth and death rates to lower birth and death rates as a country develops. It typically involves four stages: pre-industrial, transitional, industrial, and post-industrial.

Why is reproduction costly to organisms?

Reproduction is costly to organisms because it requires significant energy investment, time, and resources, which can affect their survival and ability to reproduce again in the future.

Define community. What are three properties of communities?

A community is a group of interacting populations of different species living in the same area. Three properties of communities include species richness, species evenness, and the types of interactions among species.

Define habitat

A habitat is the natural environment in which a species or population lives, providing the necessary resources for survival, such as food, water, and shelter.

Define Niche

A niche is the role or function of a species within an ecosystem, including its habitat, resource use, and interactions with other species.

Define biotic and abiotic factors

Biotic factors are the living components of an ecosystem, such as plants, animals, and microorganisms, while abiotic factors are the non-living physical and chemical elements, like sunlight, temperature, and soil.

What is meant by interspecific interactions?

Interactions between different species in a community

Competition (-/-)

a rivalry where two or more parties strive for a common goal which cannot be shared

Symbiosis (mutualism):

relationship between individuals of different species in which both individuals benefit from the association.

Commensalism

an association between two organisms in which one benefits and the other derives neither benefit nor harm.

Herbivory: What is herbivory and how have plants evolved to avoid being eaten?

the act of eating plants. thorns and thick leaves, produced defensive chemicals.

Predation

the preying of one animal on others.

What are the two types of biological mimicry

'signal mimicry' and 'cue mimicry'

'signal mimicry

occurs when mimic and model share the same receiver

Cue mimicry

when mimic and model have different receivers or when there is no receiver for the model's trait.

Parasites

an organism that lives on or in a host organism and gets its food from or at the expense of its host.

pathogens

an infectious microorganism or agent, such as a virus, bacterium, protozoan, prion, viroid, or fungus

Coevolution

evolutionary changes that occur within two or more organisms as a response to interactions between them and the resulting mutual selective pressures that those interactions cause.

species richnes

the number of species within a defined region

species evenness

describes the commonness or rarity of a species

Define an ecosystem. Which factor not present in the communities is included in the ecosystems?

a geographic area where plants, animals and other organisms, as well as weather and landscape, work together to form a bubble of life. water, air, rocks, and sunligh

food chain

linear network of links in a food web,

trophic levels

the position of an organism in the food chai

Keystone species

strongly interacting species that have a large impact on their ecosystems relative to their abundance

Energy Pyramid

a model that shows the flow of energy from one trophic, or feeding, level to the next in an ecosystem

Water cycle. What percentage of earth’s water is fresh? Out of this percentage, what further % is available for consumption

the continuous movement of water within the Earth and atmosphere. 3% of the earth's water is fresh. 2.5% of the earth's fresh water is unavailable: locked up in glaciers, polar ice caps, atmosphere, and soil; highly polluted; or lies too far under the earth's surface to be extracted at an affordable cost.

Carbon cycle

the process that moves carbon between plants, animals, and microbes; minerals in the earth; and the atmosphere

Phosphorus cycle.

the biogeochemical cycle that describes the transformation and translocation of phosphorus in soil, water, and living and dead organic material.

Eutrophication

occurs when the environment becomes enriched with nutrients, increasing the amount of plant and algae growth to estuaries and coastal waters.

oligotrophic

relatively low in plant nutrients and containing abundant oxygen in the deeper parts.

How are terrestrial and aquatic ecosystems linked?

by the movement of matter and nutrients across habitat boundaries via the emergence of aquatic insects

What are biomes? What factors are used to classify biomes?

organizes large-scale ecological variation. temperature and rainfall

Temperate grasslands

various regions north and south of the equator including Argentina, Australia, and central North America. Temperatures vary with seasons with tornadoes, blizzards, and fires

Tropical grasslands (savannas)

They are found in South America, Africa, Asia, and Australia. Tropical grasslands experience temperatures that do not drop below freezing and have distinct wet and dry seasons

Mediterranian shrublands (chaparral)

localized in the coastal areas surrounding the Mediterranean Sea including parts of Europe, North Africa, and Asia Minor. This subtropical Mediterranean biome, composed of shrub lands and woodlands. The summers are hot and dry with temperatures reaching up to 38°C (100°F). In the winter, temperatures stay around -1 °C (30°F)

Temperate deciduous forests

ocated in the mid-latitude areas which means that they are found between the polar regions and the tropics. The deciduous forest regions are exposed to warm and cold air masses, which cause this area to have four seasons.

Tropical and subtropical rain forests

moderate to highly productive ecosystems with closed tree canopies occurring at lower latitudes north and south of the equator.

Coniferous & Boreal forests

northern boreal forest, is found in 50° to 60°N latitudes. Another type, temperate coniferous forests, grows in lower latitudes of North America, Europe, and Asia, in the high elevations of mountains.

Tundra

the coldest of the biomes. It also receives low amounts of precipitation, making the tundra similar to a desert. Tundra is found in the regions just below the ice caps of the Arctic, extending across North America, to Europe, and Siberia in Asia.

Marine

From the productive estuaries and salt marshes of the coast to the deep, dark depths of the ocean floo

fresh water

ponds, lakes, streams, and rivers, and are a vital source of drinking water.

What are estuaries?

a partially enclosed, coastal water body where freshwater from rivers and streams mixes with salt water from the ocean

What is biodiversity

the variety of all living things and their interactions

What are some sources of water pollution

Sewage, Oil, landfils, etc

What are sources of air pollution

Household combustion devices, motor vehicles, industrial facilities and forest fires

Name three gases that can contribute to global warming.

carbon dioxide, methane (CH4), and nitrous Oxide (N2O)

invasive species

non-native (or alien) to the ecosystem under consideration and. a species whose introduction causes or is likely to cause economic harm, environmental harm, or harm to human health.

Natural selection

the process through which populations of living organisms adapt and change

adapatation

modification of an organism or its parts that makes it more fit for existence under the conditions of its environment

Demographs

statistis about a populations traits

Plot sampling

Estimates total number of individuals in an area

Mark-recapture sampling

individuals of a population are captured and marked with paint or a tag

Succession

a gradual change in a community’s species compostion

Pioneer species

a group of species that are the first to colonize a new habitat created by a previous disturbance

Secondary succession

community is disturbed but not destroyed

Photic zone

Where photosynthesis occurs (water)

H.I.P.P.O (Greatest loss of biodiversitsy)

Habitat loss, Invasive speices, pollution, Global climate change, Overexploitation.