2.1 Species and Populations Flashcards
Hierarchy
a system of organization in which people or groups are ranked one above the other according to status or authority. In such a system, entities are arranged in a pyramid-like structure with the highest level of authority at the top.
King Phillip Came Over From Greater Spain
An mnemonic to remember the levels of the taxonomic hierarchy: Kingdom, Phylum, Class, Order, Family, Genus, Species.
Rules for species notation
Itallics (or underlined if hand written).
Genus with a capital. Species in lower case.
Species
a group of living organisms that share common characteristics and can breed with one another to produce fertile offspring.
Binomial System of Classification
A unique genus/species combination to denote an individual “species”
Problems with using common names for species (instead of scientific names)
- Some species have multiple common names.
- Not standardized across the world.
- The same common name can be used to identify different species.
Nomenclature
The methodical, systematic way of naming organisms.
The way in which something is named.
Undescribed (species)
A species that has not undergone formal classification/naming and standardization.
Why there are more insects than any other taxa
- Short life span (fast evolution)
- High levels of resilience
- Ability to occupy small and varied niches.
Dichotomous Key
a tool that allows the identification of organisms. It is called “dichotomous” because at each step, the key presents two choices (either/or) about the characteristics of the organism or object.
No-nos when using/designing a dichotomous key
- Aways start at “number 1”
- No behavioral or habitat traits
Organism (Ecological Hierarchy)
the basic, individual units of biological structure and function, interacting with each other in populations
Population (Ecological Hierarchy)
individuals of the same species living in a specific area, sharing genetic material and interacting within their environment, contributing to the structure and dynamics of ecological communities.
Between “organism” and “community” in the ecological hierarchy.
Community (Ecological Hierarchy)
a group of interacting populations of different species living together in a particular area, forming a network of relationships that influence each other’s distribution, abundance, and evolutionary adaptation.
Between “population” and “ecosystem” in the ecological hierarchy.
Ecosystem (Ecological Hierarchy)
Between “community” and “biome” in the ecological hierarchy, and in which the biotic factors interact with the abiotic factors of an environment.
Biotic factors
The living components of an ecosystem.
Plants and animals (and dead or decomposing organic matter)
Abiotic factors
The non-living parts of an ecosystem. Rocks, soil, water, air.
Predation
One animal (the predator) kills and consumes another (the prey) for sustenance.
Herbivory
When a herbivore consumes a plant for sustenance.
Intraspecies competition
Two members of the same species competing for a shared resource, such as food or reproductive partners.
Different from interspecies competition, which involves competition between two different species.
Interspecies competition
Members of two different species competing for a shared resource such as food or space.
Different from intraspecies competition which involves competition within the same species.
Niche vs habitat
A habitat is the place an organism occupies in an ecosystem, whereas a niche is its role or function.
Habitat
The physical space occupied by an organism from which it sources resources such as shelter and food.
Fundamental niche
the full range of environmental conditions and resources an organism can potentially use and occupy without the influence of competition or other species interactions.
Separate from a realized niche, which accounts for competition.
Realized niche
the actual conditions and resources an organism uses and occupies in an ecosystem, taking into account interactions such as competition, predation, and symbiosis, which may limit its existence to a smaller subset of its fundamental niche
Competitive advantage
the traits or characteristics that allow an organism or species to outcompete others for resources, leading to greater survival, reproduction, and occupancy within a given environment or niche
Commensalism
symbiotic relationship between two species where one species benefits without affecting the other, either positively or negatively
Symbiosis
a long-term interaction between two different species, where at least one party benefits. Includes mutualism, commensalism, and parasitism
Mutualism
symbiotic relationship in which both species benefit
Parasitism
symbiotic relationship in which one species benefits to the detriment of the other
Examples of mutualism
- Bees pollinate flowers while obtaining nectar for food and energy.
- Clownfish live safely among anemones, protecting them from predators.
- Oxpecker bird eat bugs and parasites off the skin of rhinoceros.
Examples of commensalism
- Barnacles attach to whales, gaining mobility without harming the whale.
- Orchids grow on trees for sunlight, not affecting the host.
- Birds nest in trees, gaining shelter without impacting the tree.
Examples of parasitism
- Ticks feed on mammal blood, harming their hosts’ health
- Mistletoe plants absorb water, nutrients from trees, weakening them gradually.
- Parasitic wasps lay eggs inside caterpillars, larvae consume host internally.
Ecology
the scientific study of interactions among organisms and their environment
Survivorship
refers to the proportion of individuals in a population surviving to different ages, often illustrated by a survivorship curve
Post reproductive survivorship
refers to the period in an organism’s life after it has stopped reproducing, focusing on the survival rates and longevity of individuals during this phase.
Pre reproductive survivorship
refers to the phase of an organism’s life from birth until it reaches sexual maturity, focusing on the survival rates of individuals before they are capable of reproduction.
Humans have a high pre-reproductive surivorship
Frogs have a low pre-reproductive survivorship.
r-selected species
characterized by high reproductive rates, short gestation, early maturation, and a strategy focused on producing a large number of offspring with low survival rates.
As opposed to “K-selected species”
K-selected species
characterized by lower reproductive rates, longer gestation periods, late maturation, and a strategy focused on producing fewer offspring but with higher investments in parental care and survival.
As opposed to r-selected species.
J-curve
illustrates exponential growth in which a population size increases rapidly and without apparent limit over time.
S-curve
a pattern of population growth that starts rapidly, then slows as the population approaches its carrying capacity
As opposed to a “J-shaped curve”
Density dependent limiting factor
an ecological factor whose effects on a population vary depending on the population density, typically intensifying as the population size increases.
Limiting factor
an environmental condition that restricts the growth, abundance, or distribution of an organism or a population within an ecosystem
Carrying Capacity
the maximum population size that an environment can sustain
Exponential
Rapid growth. Not linear. Short doubling time. Forms a “J-shaped curve”.
