Adaptations to the Physical Environment

Flashcards covering key concepts from the lecture on environmental adaptations, focusing on tolerance limits, evolutionary roles, and various adaptive responses.

What are the physical (abiotic) factors that limit an organism’s growth and survival?

Food, Water, Temperature.

What does Shelford's Law of Tolerance state?

There are upper and lower limits to the physical factors an organism can tolerate.

How do different species respond to their limits of tolerance?

Different species have different factors that limit their growth and ranges of tolerance.

What happens to an organism's fitness beyond its tolerance limits?

An organism's fitness is compromised, often due to its inability to maintain internal homeostasis.

How does evolution shape the tolerance curves of species?

If the environment changes, individuals with better tolerance may be favored by natural selection, shifting the population's tolerance limit.

What types of conditions change over time in an environment?

Temporal variability can be predictable (seasonal, diurnal, tidal) or unpredictable.

What is the Principle of Allocation in regards to adaptations?

Adaptations to one challenge may reduce or preclude adaptations to others, leading to evolutionary trade-offs.

What are the two categories of adaptive responses to environmental changes?

Avoidance and Adaptations.

What is the benefit of hibernation for animals?

Avoidance of harsh conditions and protection against predators.

What are the costs associated with migration?

Considerable energy costs and high risk of mortality.

How do desert mammals conserve water during evaporation?

By allowing body temperatures to rise above normal during the hottest part of the day and not panting or sweating.

What adaptations do desert rodents have for water conservation?

They produce hyperosmotic urine and can metabolize water from carbohydrates.

What are osmoconformers and osmoregulators?

Osmoconformers maintain internal osmotic balance with the environment, while osmoregulators control their internal osmotic concentrations.

What adaptations do plants have to prevent desiccation?

Waxy cuticles and mechanisms for water transport from roots to leaves.

What is the relationship between stomata and photosynthesis in hot, dry climates?

Stomata must be open for CO2 uptake, increasing water loss; C4 photosynthesis is favored to reduce water loss.