Insects make up
the highest proportion of earth's organism
- 5 mill yet to be discovered
- make up 50% of species
Biodiversity
number and variety of species in an ecosystem
Insect biomass
* ants and termites present 33% of all animal biomass in Amazonian rainforest
number of individuals per species impressive
Adaptive radiation
* determined by the richness of plants species which insects feed
evolutionary divergence of members in a single lineage INTO a series of adaptive zones with different niches
Adaptive zone
life common group of characterized species mechanisms to exploit it
Radiation of beetles have many adapative zones such as
* most diverse in the planet
- leaf feeding
- wood boring
- dung feeding
- aquatic predators
What are the setbacks for Biodiversity?
Be measured at any scale
** Due to size
** Numerous species hard to get through
** Alot of representation of biomass so the chances of counting the same species twice will be high
Mouthpart adaptation allow insects
to diversify their nutritional resources
Mouthparts may vary between immature and adult species, causing
** gives rise to biodiversity bc they give them better adaptation
Separate ecological niches
What adaptations give rise to insect biodiversity?
- Flying
- Metamorphosis
- Diverse niches
Adaptive radiation
* determined by the richness of plants species which insects feed
Evolutionary divergence of members in a single lineage INTO a series of adaptive zones with different ecological niches
Coevolution
when two or more species impact each others evolutionary trajectory
Half of all insect species are
phytophagous
More than 2/3 of flowering plants are
insect pollinated
Plants have developed specific traits to
attract/trick insects into pollinating them
Ex. Proboscis(a long stem connected to an animal used to pollinate)
Fun Fact: Xanthopan Morganii praedicta was observed feeding on nectars of orchids and transferring pollen
...
Fig tress are pollinated by
fig wasps
Female fig wasps will enter the syconium (false fruit)
to lay its eggs{ carries them into new place}
Selective pressure have led to
Ex. german cockroaches
insects adapted to human environments such as our food, homes
Aedes aegypti
* constrained in forests of Africa
yellow fever mosquito
* well adapted to urban environments
* Anthropophilic - an important vector
german cockroaches are not found in
natural environments, only their close relatives
Ae. aegypti aegypti developed preference for
human scent, spread alongside ppl
Termites require
* trichonympha found in guts
symbiotic flagellates to digest cellulose
Aphids require symbiont to
provide amino acids
Loiasis
* Filarial worms spread by deerflies
migrate to surface of skin when flies are most active
Malaria
has required both mosquitoes and human host to complete reproduction and development