Ecology

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Ecology (生態学)

Mount Usu / Sarobetsu post-mined peatland
From left: Crater basin in 1986 and 2006. Cottongrass / Daylily

HOME > Lecture catalog / Research summary > Glossary > Biology > Ecology

A model should be as simple as possible. But no simpler. (Einstein)

The derivation of word 'ecology'

Ecology (Oecology, Oekologie) = Eco + logy =

Oikos (=household or at home) + Logos (logics)

Cf. economy: ecology surveys energy flow and economics surveys money flow; viz. "Economics" deals with functional housekeeping, and "Ecology" deals with environmental housekeeping.

Definition

The totality or pattern of relations between organisms and their environment
If there are 100 ecologists, there are 100 kinds of definitions.

The study of life on organisms (= environmental biology)
General physiology about all organisms (narrow sense)
The science of population (Clements)
The scientific natural history - science of living things' economy and society (Elton 1927)
The science dealing with the structure of nature or ecosystem, and Its relation to other sciences and its relevance to human civilization (Odum 1971)
Study of the inter-relationships between organisms and their environments (Pianka 1978)

Classification (分類)

Principles and concepts pertaining to the ecosystem

Scale or level

Synecology: Community ecology, ecosystem ecology, production ecology, etc.
Autoecology: Population ecology, genecology, sociobiology, etc.

Materials

Animal ecology, plant ecology, fungal ecology, bacterial ecology, etc.

Study area

Ocean ecology, terrestrial ecology, alpine ecology, wetland ecology, etc.

[Lectures: environmental conservation, environmental sicences, HUSTEP]

Hierarchy (階層)

The focus of ecology is on the levels of organization from organisms to ecosystems (or nature).
Table. Levels of organization spectrum. Ecology focuses on the top-and portion of the spectrum; viz. the levels of organization from organisms to ecosystems (modified from Odum 1971 & Krebs 2000). Any more level aids in the study of another level, but never completely explains the phenomena occurring at that level.

Top-down
⇓ nature
⇓ landscapes
⇓ ecosystems (biosystem)
⇓ communities (biome)
⇓ species
⇓ populations
⇓ organisms (individual)
⇓ organs
⇓ cells
⇓ subcellular organelles
⇓ genes
⇓ molecules

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⇔ ⇅ energy
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⇔ ⇅ matter
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ecosystem (biosystem)

population system
organismic system
organ system
cell system

genetic system

Bottom-up

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Animal ecology (動物生態学)

A study of the relationships of animals to their environments
☛ Estimation of population density (個体数推定)

Territory (縄張り)

Any defended area by an organism or a group of similar organisms (Noble 1939)

Purposes: mating, nesting, roosting, feeding, edt.

Home range (s.s., 行動圏)

not associated with aggressive behaviour, as seen in territory (parts of the home range may be defended)

Group (群れ)

Summary as general use:
Herd: a group of herbivorous animals in a species living and feeding together

Ex. Elephants, deer and moose, giraffes (also used tower), hippo, whales, antelope. Sea urchins

Pride: lions, peacoks (also used muster and ostentation)
Pack: dogs, including coyotes, wolves and hounds, weasels

Clowder: cats (kindle for kittens) - not so common

Litter: kittens, uppies and pigles (at one time)

Troop: monkeys, apes
Flock: brids, including geese. livestock such as goats and sheep

Murder: crows and ravens. Parliament: owls. Gang: turkeys.
Flight: swallows. Gaggle: geese.

Pod: dolphins, whales, pelicans, seals, walruses
Army: frogs, ants
School (shoal): fish
Herd behavior: the behavior of individuals in a group acting collectively without centralized direction ☛ Economics

Hierarchy (順位)

boss > sub-boss > males > …

Society (社会)

Def. (in ecology): a group of individuals in the same species interacting and coexisting within a shared environment

Interaction: cooperation, competition, and various forms of social organization that influence survival and reproduction
Ex. ant colonies, wolf packs, bird flocks

Def. Parental care (子育て): parental investment being made to the evolutionary fitness of offspring
Paternal care (父親保育), by the father
Maternal care (母親保育), by the mother
Biparental care (両親保育), by the parents

Alloparental care (他子保育), by individuals other than the biological parents of an offspring

Ecochemicals (生態相関物質)

1959 Butenandt AFJ (1903-1995): C₁₆H₃₀O extracted from Bombyx mori

CH₃(CH₂)₂CH=CHCH=CH(CH₂)₈CH₂OH, named bombykol →
firstly-discovered sexual pheromone

Urban ecology (都市生態学)

Structure and dynamics of urban environments

urban ecosystem - bioecological approach
urbanization(some impact) - bad case: self-domestication
→ indicator of urbanization → consider the merit and demerit of urban