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Species-area relationship:

• Species-area exponent (z) typically falls between 0.1 and 0.3.

Ecological niches:

• Pianka index ranges from 0 (no overlap) to 1 (complete overlap).

Population growth models:

• Exponential growth model: dN/dt = rN
• Logistic growth model: dN/dt = rN(1 – N/K)

Population dynamics:

• Birth rates: typically expressed as the number of individuals born per 1000 individuals per year.
• Death rates: typically expressed as the number of individuals died per 1000 individuals per year.
• Immigration and emigration: typically expressed as the number of individuals entering or leaving a population per 1000 individuals per year.

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Biodiversity:

• Estimated number of species on Earth: 8.7 million

Ecological adaptations:

• Camouflage: degree measured using the percentage of predators that fail to recognize it.
• Mimicry: degree measured using the percentage of predators that mistake it for another species.
• Thermoregulation: measured using the range of temperatures an organism can survive in.

Symbiotic relationships:

• Mutualism: the degree of mutualism between two species is often measured using the percentage of individuals of each species that benefit from the relationship.
• Commensalism: the degree of commensalism between two species is often measured using the percentage of individuals of one species that benefit from the relationship, while the other species is neither harmed nor helped.
• Parasitism: the degree of parasitism between two species is often measured using the percentage of individuals of one species (the host) that are harmed by the relationship, while the other species (the parasite) benefits.