Entomology
Week 2
Graham Holloway
Insect Development and Lifecycles
Functional Approach;
1. Development and differentiation
2. Food / other resource acquisition
3. Dispersal / resource tracking
4. Mating/ mate selection
5. Allocation of resources to offspring
6. Selection of sites for offspring growth
7. Oviposition
- Niche separation -adults/larvae feed differently
- Some life histories separate dispersal and resource tracking // resource acquisition –
adults feed very little
- Arisen independently multiple times in insect evolution
- Aqueous carnivorous larvae // adults don’t feed; mate and deposit eggs –
Ephemeroptera / plerotera / trichopteran
- Lepidoptera similar/ adults energy from sipping nectar
- Some adults have dispersal/mating/resource tracking and acquisition
- Provisioning, finding food for offspring [orthoptera / coleoptera/ Diptera]
- Hymenoptera; evolution of eusocial behavior
Apterygote; ametabolous
- Seasonal migration between costal caves and inland = trigoniophthalmus alternatus //
no metamorphosis, immature resemble adults but with no genitalia
Exopterygote; hemimetabolous
- Incomplete metamorphosis is odonatan/ ephemeroptera/ zoraptera/ dermaptera/
plecopteran/ orthoptera/ Phasmatodea/ matnodea/ blattodea/ isoptera/ Thysanoptera/
hemiptera/ psorodea
- Migratory locusts; wing bud appears 3rd instar – not fully formed until adult moult
[uneven/ allometric growth – head/thorax proportionally larger in nymphs than adults]
- Periodical circada; live as nymphs feeding on tree roots/ 13-17 years development =
emergence holes
- Teneral insects; recently molted with exoskeleton not hardened and not final
coloration [vulnerable/ pale/ possibly mobile]
- Exuviae; cast/discarded skin of insect
- Mating and oviposition; [expulsion of egg from oviduct to external environment]
o Oviposition slits [egg-laying appendage on F “ovipositor” slits branches to
create egg nests = nurseries]
Edopterygote Insects;
Week 2
Graham Holloway
Insect Development and Lifecycles
Functional Approach;
1. Development and differentiation
2. Food / other resource acquisition
3. Dispersal / resource tracking
4. Mating/ mate selection
5. Allocation of resources to offspring
6. Selection of sites for offspring growth
7. Oviposition
- Niche separation -adults/larvae feed differently
- Some life histories separate dispersal and resource tracking // resource acquisition –
adults feed very little
- Arisen independently multiple times in insect evolution
- Aqueous carnivorous larvae // adults don’t feed; mate and deposit eggs –
Ephemeroptera / plerotera / trichopteran
- Lepidoptera similar/ adults energy from sipping nectar
- Some adults have dispersal/mating/resource tracking and acquisition
- Provisioning, finding food for offspring [orthoptera / coleoptera/ Diptera]
- Hymenoptera; evolution of eusocial behavior
Apterygote; ametabolous
- Seasonal migration between costal caves and inland = trigoniophthalmus alternatus //
no metamorphosis, immature resemble adults but with no genitalia
Exopterygote; hemimetabolous
- Incomplete metamorphosis is odonatan/ ephemeroptera/ zoraptera/ dermaptera/
plecopteran/ orthoptera/ Phasmatodea/ matnodea/ blattodea/ isoptera/ Thysanoptera/
hemiptera/ psorodea
- Migratory locusts; wing bud appears 3rd instar – not fully formed until adult moult
[uneven/ allometric growth – head/thorax proportionally larger in nymphs than adults]
- Periodical circada; live as nymphs feeding on tree roots/ 13-17 years development =
emergence holes
- Teneral insects; recently molted with exoskeleton not hardened and not final
coloration [vulnerable/ pale/ possibly mobile]
- Exuviae; cast/discarded skin of insect
- Mating and oviposition; [expulsion of egg from oviduct to external environment]
o Oviposition slits [egg-laying appendage on F “ovipositor” slits branches to
create egg nests = nurseries]
Edopterygote Insects;
