insects 1 (importance) Flashcards
importance of insects
disease e.g. Malaria
destroys crops
pollinators
critical in the ecosystem
used for nutrient recycling
how many insects are alive right now
10 quintillion insects
200 000 000 for every human
make up majority of different animal species that exist
why insects are successful
huge diversity in species, size, habitats and appearance
insect diversity in life cycle/longevity
majority of insec5s have a life cycle of about one year
short gestation cycle of two weeks
however queen termite lives 60 years
insect diversity: diet
locust: biting and chewing
- destroys crops
aphid: piercing and sucking
- feeding damage and transits disease
horse fly: biting and sponging
- nuisance and damage cattle
mosquito: piercing and sucking
- disease transmission
insect diversity: sociality
Solitary: e.g. preying mantis, locust, bees
* Gregarious (act as individuals but aggregate in
groups): e.g. locust, collembola, bees
* Sub-social (most primitive level of interaction
involving parents and offspring): e.g. wasps, bees
* Highly social (complex social “caste” system):
e.g. ants, bees, termites
reasons for success and diversity
exoskeleton, long history, short generation time and fecundity; metamorphosis; adaptability to changing environments; small size; evolutionary interactions with other organisms; sociality; mobile winged adults and passive dispersal
common anatomical features
body has three parts
head: one pair of antennae and mandibles; 2 pairs of maxillae
Thorax: 3 pairs of legs; usually 2 pairs of
wings
Abdomen: no locomotory appendages;
genital opening usually at posterior end
Post-embryonic development requires
metamorphosis
classification of insects
in class insecta
two subclasses: Apterygota and Pterygota
sub-class Pterygota has two divisions:
Exopterygota (AKA Hemimetabola). Endopterygota (Holometabola)
insect orders
some variation in classification bc scientists don’t always agree
normally 29 orders:
- 4 Apterygota
-25 Pterygota
subphylum which insects are in
subphylum: Hexapoda. this has two classes: Entognatha (Collembola/springtails) and Insecta
Insect sub-classes
sub-class Apterygota and Pterygota
in Pterygota there s Infra-class Paleoptra and Neoptra.
Neoptra contains Exopterygota and Endopterygota
Exopterygota Superorder
AKA Hemimetabola
develop wings on outside
include Hemiptera (true bugs), Blattodea (cockroaches and termites), and Orthoptera (locusts and grasshoppers)
Endopterygota super order
AKA Holometabola
wings develop on inside
includes Diptera (ture flies), Cleoptera (beetles) and Lepidoptera (butterflies and moths)
