Unit 9 Ecology

The Principles of Ecology UNIT 9 : ECOLOGY The Principles of Ecology Ecology – study of the interactions among living things and their surrounding. Name comes from Greek word “oikos”- meaning “house”.  

Levels of Organization Organism – an individual living thing example:   

Population – group of same species that lives in one area example:

Community – group of different species that live together in one area example:  

Ecosystem – includes all organisms as well as the climate, soil, water, rocks, and other non-living things in a given area. example:  

Biome – major regional or global community of organisms characterized by climate conditions and plant communities that thrive there. example:  

Biosphere – portion of planet where life exists 2 miles (↨)  

Ecological research methods include observations , experimentation, and modeling Observation – the act of carefully watching something over time.   May be long term or short term studies Surveys are used to monitor and observe populations

Experimentation – may perform experiments in the lab or in the field   lab experiments give researcher more control, but artificial setting does not reflect complex interactions that occur in nature. field experiments gives more accurate picture but is more difficult because of numerous factors at work in nature.

Modeling – use of computer or mathematical models to describe and model nature based on real data.     Can see how one variable affects another Can create virtual ecosystem

Biotic and Abiotic Factors An ecosystem includes both biotic and abiotic factors Biotic – includes living things

Abiotic – includes nonliving things such as moisture, temperature, wind, sunlight, and soil

Changing one factor in an ecosystem can affect many other factors Biodiversity – the assortment, or variety, of living things in an ecosystem amount depends on many factors tropical rainforests have large biodiversity

Keystone species – a species that has an unusually large effect on its ecosystem loss of this species may cause ripple effect felt across entire ecosystem

Example: beaver changes habitat for many other species by creating ponds

Symbiotic Relationships Symbiosis- two species living together 3 Types of symbiosis: 1. Commensalism 2. Parasitism 3. Mutualism Cleaning shrimp

Symbiotic Relationships Commensalism- one species benefits and the other is neither harmed nor helped Ex. orchids on a tree

Symbiotic Relationships Commensalism- one species benefits and the other is neither harmed nor helped Ex. polar bears and cyanobacteria You can see here that this polar bear is no longer white.

Symbiotic Relationships Parasitism- one species benefits (parasite) and the other is harmed (host) Parasite-Host relationship

Symbiotic Relationships Parasitism- parasite-host Ex. lampreys, leeches, fleas, ticks, tapeworm

Symbiotic Relationships Mutualism- beneficial to both species Ex. cleaning birds and cleaner shrimp The Egyptian plover takes insects from the backs of buffaloes, giraffes and rhinos. The plover has also been observed taking leeches from the open mouths of crocodiles! In this association the plover receives a supply of food and the other animal rids itself of unwelcome pests

Symbiotic Relationships Mutualism- beneficial to both species Ex. lichen The Egyptian plover takes insects from the backs of buffaloes, giraffes and rhinos. The plover has also been observed taking leeches from the open mouths of crocodiles! In this association the plover receives a supply of food and the other animal rids itself of unwelcome pests

X = 1 species Type of relationship Species harmed Species benefits Species neutral Commensalism X Parasitism Mutualism XX X = 1 species