Lecture 1 Flashcards
Study of Insects: _____; covers the total range of biological disciplines,
including
Entomology - evolution, ecology, behavior, anatomy, physiology, biochemistry, and genetics.
10 species in 1; DNA barcoding reveals cryptic species in the neotropical skipper butterfly
Astraptes fulgerator
7 taxa coded according to their
primary food plants:
TRIGO, CELT, LONCHO, LOHAMP,
HIHAMP, BYTTNER, and
INGCUP
3 taxa are coded by their main
food plants plus a color
character of the adult:
SENNOV, YESENN, & FABOV
Biologists work with insects for many
reasons:
- ease of culturing in a laboratory,
- rapid population turnover, and
- availability of many individuals
Insects are essential to the following ecosystem functions:
- Food Chains
- Feeding Specializations (ingestion of detritus, rotting materials, living and dead wood, and fungus)
- Aquatic filter
- Herbivory (=phytophagy)
…..
Insect herbivory accelerates ___ and increases ____
- nutrient cycling
- leaf-litter and wood degradation,
dispersal of fungi, disposalof carrion and dung, and soil turnover
-plant production
Insects are essential to the following ecosystem functions:
6. _____, including ___
- ____ via ___
- plant propagation,
pollination and seed dispersal; - maintenance of plant community composition and structure,
- phytophagy (endophyticfeeding), including seed feeding;
insect feeding on plant or fungal tissues that occurs within tissue of a
living plant, whether the specific plant tissue is live or dead
Endophagy
➢ Some insects are considered ___
❖because loss of their critical ecological functions could collapse the wider ecosystem.
keystone species
IOI 1. __ convert cellulose in tropical soils, suggesting that they are keystones in
tropical soil structuring.
- Termites
IOI 2. ____ provide us with honey but are also valuable agricultural pollinators worth an estimated US$15 billion annually in the USA.
- Honey bees
- 1000 colonies
- USD 59,488
(3) ___ as effective biological control
agents
> form of physiological manipulation
- Parasitoid wasps
a parasitoid that attacks hosts
that continue to feed and grow
during the course of parasitism,
only arresting host development
just prior to parasitoid pupation
Endoparasitic koinobionts
Parasitoids of hoverflies
- Subfamily Diplazontinae
(Ichneumonidae), - Figitidae (Superfamily Cynipoidea),
- Encyrtidae
- Pteromalidae (Chalcidoidea)
- Megasplidae (Ceraphronoidea)
(Syrphidae: Diptera)
➢ feed on nectar and pollen and are
important pollinators of flowering
plants in wild and agricultural
ecosystems.
➢ larvae are insectivorous, feeding on aphids and some other Homoptera (whiteflies and leafhoppers).
Adult hoverflies (Syrphidae: Diptera)
are koinobiont parasitoids,
attacking egg or early larval
stages of their host and
egressing as adults from the
pupae
Ichneumonidae
IOI 4. Insects contain a vast array of
____, some of which can be collected, extracted, or synthesized for our use.
- chemical compounds
CC:
1. Increases stimulation of pain nerves. Particularly high concentration in hornet strings.
- Causes constriction of blood vessels, resulting in reducing blood flow and increasing blood pressure.
- Major component of some ant venoms; spray
- Acetylcholine
- Noradrenaline
- Formic Acid
Chemical components of Insect Venom
1. Splits carbs from their complexes w/ proteins and breaks them down, allowing penetration of venom into tissue
- Causes degranulation of mast cells, leading to release of inflammatory agent histamine
- Can pass through the blood-brain barrier, act on the central nervous system, and block ion channels
- Hyluronidase
- MCD Peptide
- Apamin
Chemical components of Insect Venom
1. Acts as an irritant and contributes towards the pain experienced as a result of the venom
- Present only in small amounts. Any effect is largely obscured by other components of venom
- A peptide, and a major toxic component of bee venom. Can break up & kill cells.
- Seratonin
- Dopamine
- Melittin
Chemical components of Insect Venom
- An enzyme that breaks up cell membrane & destroys cells. Also a strong allergen.
- An enzyme, with an effect similar to phospholipase A. These enzymes also help immobilise prey.
- Signal and attract other nearby insects of the same species to take defensive action.
- Phospholipase A.
- Phospholipase B.
- Alarm Pheromones
Chemical components of Insect Venom
1. A peptide that forms a large potion of wasp venom. Its components have yet to be fully characterized
2. A peptide that forms a large portion of hornet venom. Its components have yet to be fully characterised.
3. Can contribute to pain and itching. It is also one of the chemicals released during an allergic response
- Wasp Kinin
- Hornet Kinin
- Histamine
a component of insect cuticle, and its derivatives act as anticoagulants, enhance wound and burn healing, reduce serum cholesterol, serve as non-allergenic drug carriers, provide strong biodegradable plastics, and
enhance removal of pollutants from
waste water, to mention just a few
developing applications.
- Chitin
IOI (5)
Silk from _____ and related species has been
used for fabric for centuries, and two
endemic South African species may be increasing in local value.
Silk from the cocoons of silkworm
moths, Bombyx mori.
IOI (6) The ____ is
obtained commercially from scale
insects of ____
cultured on _____
red dye cochineal
Dactylopius coccus
cultured on Opuntia cacti.
IOI (7)
Another scale insect, the lac insect
___ , is a source of a
Kerria lacca
commercial varnish called shellac.
IOI (8) characteristics of certain insects make them useful models
for understanding general biological processes (ex)
model research organism.
IOI (9) The field of ___ owes
its existence to entomologists’ studies of social insects.
sociobiology
___, in which the size of individual organisms is approximately proportional to the number of described species in the
higher taxon that it represents.
Speciescape
Insecta percenage
83%
PH new record: 51 species
499 family
Insects family percentage (Top 5)
Diptera - 63%
Lepidoptera - 12 %
Hymenoptera - 9%
Coleoptera - 4%
Hemiptera - 3%
Drosophila melanogaster generation time
embryo- 24 hrs
1st instar larva- 24 hrs
2nd instar larva- 24 hrs
prepupa- 2-3 days
pupa to female - 5 days
Individuals only meet at random or for mating
Solitary (Mating, Aggression)
Parental brood care
Subsocial
Aggrregation in transient or permanent groups (e.g for predator defense)
Communal/gregarious
Transient or permanent groups with reproductive division of labor, cooperative brood care and at least two co-occuring generations
(Primitively) eusocial
