Entomology is the study of insects. There are over 750,000 identified insect species worldwide, with only around 10,000 species harmful to humans. Insects are classified and grouped by features like feeding habits and mouthparts. They have external skeletons and are composed of segments including the head, thorax, and abdomen. Insect life cycles can involve incomplete or complete metamorphosis through stages like eggs, larvae, pupae, and adults. Key concepts in entomology include classification, orders of insects, life cycles, and approaches to pest management.

1. Entomology
Original PowerPoint by
Mark Morgan
Modified by Georgia
Agriculture Education
Curriculum Office

2. What is
Entomology?
- the branch of zoology
that deals with the
study of insects

3. • On average there are more
than 750,000 species of
insects that have been
identified worldwide.

4. • There are only
approximately 10,000
species of insects that
are harmful to humans.

5. Problems
– Deadly epidemics of
the past have been
caused by diseased
organisms carried by
insects.
– Example: Bubonic
Plague epidemic that
wiped out the
population of Europe
in the 14 century was
carried by fleas that
infested rodents

6. Classification of
insects:
– Kingdom
– Phyla
– Class
– Order
– Family
– Genus
– Species

7. • The highest level is the
Kingdom
• The most specific is the
species level.
• Organisms are usually
classified by the genus
and species.
• This is called a binomial
nomenclature.

8. Six orders of
insects:
- Orthoptera- which
includes the grasshopper
and locust
– Hemiptera- which
includes the true bugs
such as leaf hoppers and
plant bugs
– Lepidoptera – moths and
butterflies
– Homoptera- aphids

9. Cont’d…
– Thysanoptera- thrips
– Coleoptera- which is
the largest group of
the insect orders this
has beetles

10. How are insects
grouped?
• by the way they feed on
plants
• by their mouth parts

11. Six Mouth Parts
– Sponging
– Rasping- sucking
– Siphoning
– Chewing-lapping
– Chewing
– Piercing- sucking

12. • Insects have no internal
skeleton and they rely on
their hard outer coating,
exoskeleton, which
protects their inner
organs and supports
their body.

13. Parts of an Insect
– Head
– Thorax
– Abdomen

14. Head
– Has a pair of
compound eye and
two sensory
appendages called
antennae

15. Thorax
– is divided into three
segments from which
are attached three
pairs of legs

16. Abdomen
– is attached to the
thorax
– which will contain
more segments

17. Life Cycles
– Incomplete
Metamorphosis
– Complete
Metamorphosis

18. Incomplete
Metamorphosis
• Eggs
• to Early nymph (no
wings)
• to late nymph (wings
developing)
• Goes to Adult

19. Complete
Metamorphosis
• Eggs to
• Larva to
• Pupa to
• Adult

20. What Is a Larva?
• It is when the young
insect has soft tubular
body and looks very
much like a worm

21. What Is the Pupa
Stage?
• The larva matures and
will pass through the
pupa stages which is
usually a relatively
dormant stage.

22. What is DDT?
– This is a chemical that
was discovered by
German name Othmar
Zeidler in 1874.
– It is a chemical used to
reduce the number of
insects in a given area.
– Example: mosquitoes in
the tropics

23. Integrated Pest
Management
• Cultural methods
• Insect diseases and
predators
• Pheromones
• Release of sterile
males
• Insect resistant
plants varieties