The document discusses the history of insect ecology, highlighting its emergence as a distinct scientific discipline in the early 20th century, with contributions from notable figures such as Ernst Haeckel and Charles Darwin. It defines ecology as the study of interactions among organisms and their environment, encompassing both biotic and abiotic components. Additionally, the document details the ecological influences on insect populations and significant advances in ecological theory throughout the 20th century.

1. History of insect ecology ( Term Paper)
History

2.  The term ecology was coined by a German biologist
Ernst Haeckel (1869) in his publication of “Generalle
morphologie des organixmen”.
 Literally ecology signifies study of earth’s household
comprising of the plants, animals, micro-organisms and
people that live together as interdependent components.
 Insect ecology is the scientific study of how insects,
individually or as a community, interact with the
surrounding environment or ecosystem.
 Insects play significant roles in the ecology of the world
due to their vast diversity of form, function and life-style

3. History:
Ecology is a new science, emerged as a
distinct discipline only at the turn of
the 20th Century & became prominent
in the second half of 20th Century.
Ernst Heinrich Philipp August
Haeckel, was an eminent German
biologist, naturalist, philosopher,
physician, professor and artist who
described thousands of new species
and coined many terms in biology,
including phylum, phylogeny , etc

4. Antonie van Leeuwenhoek
1632–1723
First to develop concept of food chains and population
regulation.
Carl Linnaeus - Influential naturalist
 1707–1778
 Showed some modern concepts of ecology such as food
chains: smaller and weaker animals are usually attacked
by the larger and stronger ones
 Developed the idea of equilibrium in nature in “politica
Naturae”
Alexander von Humboldt- A German naturalist
1769–1859
father of ecology
first to take on the study of the relationships
between organisms and their environment.

5.  Charles Darwin
1809–1882
Founder of the hypothesis of evolution by means of
natural selection, founder of ecological studies of
soils
 Nicholson-1933
Introduced modern conceptual models of insect
populations

6.  Later Foundations for modern ecology were laid in
the early work of plant and animal physiologists.
In the early and mid 1900s, the works started with
the general effects of meteorological conditions to
insect life such as, climate , weather, temperature,
RH, rainfall, water balance ,etc.
Charles H.T. Townsend(1924) studied about insect
environment, media factors, controls, measurement
of factors and the response.

7. Some important ecological advances in the 1900s
 1913: V.E. Shelford’s_ Law of Tolerance
 1917: Joseph Grinnel’s_ Concept of niche
 1922: R.H.Yapp’s_ Concept of habitat
 1926: Volterra’s_ Simple predator-prey model
 1927: C.E. Elton’s_ ecological niches in insects
and pyramids of numbers
 1934: Gause’s_ Competitive exclusion
principle.
 Modern ecology came of age in 1942 with the
development by R.L.Lindeman of the United
states of the Tropic- dynamic concept of
ecology.

8. Environment and components of environment
(Review paper)

9. Environment is a natural unit
consisting of all plants, animals and
micro-organisms (biotic factors) in
an area functioning together with
all of the non-living physical
(abiotic) factors of
the environment.
An environment comprises of two
basic_components
1.Abiotic_Components
2.Biotic_Components

10. 1.Physical factors (abiotic factors) such as temperature,
wind, humidity, light and pesticides.
2.Biological factors (biotic factors) It comprises the living
part of the environment, which includes the association of a
number of interrelated populations belonging to different
species in a common environment.
such as other members of the same insect species; food
sources; natural enemies (including predators, parasitoids
and diseases) and competitors (other organisms that use the
same space or food sources).

11. Abiotic components Biotic components

12. Environment of an insect population consists of:
Abiotic factors:
•temperature: The bulk of insects die on 40-60°C (killing effect depends
on the duration of high temperature)
•humidity: adult insects emerge earlier in case of dry soil/litter;
wireworms can move slower in wet soil
•light: nocturnal insects (active during the night) and diurnal insects
(active during the day)
•medium (soil) : Agriotes spp. (click beetles) wireworms prefer soils with
4.0-5.5 pH
Biotic factors:
•members of the same species (homotypal effects)
•members of other species (heterotypal effects)
•nourishment, food source
Anthropogenic factors:
•impacts of human activities