Understanding Ecology: Key Concepts and Adaptations

Ecology: Organisms and Their Environment

Ecology: The study of the interactions of organisms with each other and the environment.

Ecological Factors

Ecological factors: These are the characteristics of the environment that affect living things. They can be abiotic or biotic.

Limiting Factors

Limiting factor: The one that is closest to the value at which an organism cannot develop properly.

Adaptation

Adaptation: The evolutionary adaptation of organisms to a given environment. Eurioic agencies and organizations are examples.

Adaptations to Water Shortages

  • Water storage in special tissues.
  • Drought-resistant seeds.
  • Leaves with few stomata.
  • Extensive and profound root systems.
  • Small, hard leaves.

Adaptations to Temperature Changes

  • Production of sweat.
  • Inactivity during the day.
  • Nocturnal life.
  • Panting.
  • Subterranean habits.

Adjustments to Salt Concentration

  • Some shrubs secrete salts and deposit selected salts in the soil.
  • The cells of invertebrates have the same concentration of salts as the external environment.
  • Osmotic regulation in freshwater fish.
  • Osmotic regulation in saltwater bony and cartilaginous fish.
  • Seabirds expel salt through salt glands.

Adaptations to Lack of Oxygen

  • Increasing the number of red blood cells and hemoglobin.
  • Increase in pulmonary ventilation.

Adaptations to Lack of Food

  • Storage of reserves in the body.
  • Storage of food in hidden places.
  • Migration in search of food.

Environmental Changes and Living Things

Living organisms produce changes in the environment. They also produce changes in the environment due to biological action. Vegetation has a major influence on climate. There are also changes in the field produced by some living things.

Populations

Population: A group of organisms belonging to the same species living in the same territory and able to interbreed.

Types of Populations:

  • Colonial: Organisms are interconnected and reproduce asexually.
  • Family: Descendants come from a pair of animals and remain together.
  • State: Populations originate from a female founder, with anatomical and physiological differences.
  • Gregarious: Living together to help each other.

Dynamics of Populations

Biotic Potential: The difference between the birth rate and death rate.

Pyramid of Age: A graphical representation of the age distribution of individuals in a population.

Communities

Community: A group of organisms living in the same area and interacting with each other.

Biodiversity: Variety of species in a community.

Community Dynamics

Ecological Succession: A sequence of communities that occur over time.

Primary Succession:

  1. An uninhabited area is colonized by pioneer species with minimal nutritional requirements.
  2. The soil is enriched, progressively increasing biodiversity.
  3. Evolution ends, resulting in a progressive community with a maximum degree of stability, called climax.

Secondary Succession:

When a community loses an important part of its populations, it is said to have suffered a regression. After the regression, a new evolutionary process starts.

Soil

Soil: The medium where plants grow and animals live. The soil is a mineral component interacting with other organic components.

Interspecific Relations

  • Predation: An organism feeds on another that it kills.
  • Parasitism: An organism lives off another, obtaining food and harming it.
  • Competition: Two species strive for the same resource.
  • Phoresy: A special type of parasitism where one species takes advantage of another, but not for food.
  • Commensalism: One species obtains food from debris left by another.
  • Inquilism: One species finds protection or shelter in another of a different species.
  • Symbiosis: Two species are mutually beneficial.
  • Mutualism: A biological interaction similar to symbiosis, but the union is not permanent and essential.