Insects and people final

5 major orders of insects

Coleoptera, Lepidoptera, Diptera, Hymenoptera, Hemiptera

Coleoptera

beetles, largest order of insects

Lepidoptera

butterflies/moths

Diptera

flies

Hymenoptera

bees/wasps/ants

Hemiptera

true bugs/plant hoppers/cicadas

Common anatomy of insects

six legs, jointed appendages, 1 pair of antennae, exposed mandibles, ocelli, exoskeleton, segmentation, symmetrical, no spine, Malpighian tubes, tracheal system

Why are insects so diverse?

small size, reproduce and die quickly, ability to fly, long time since ancestral insect, associations with other organisms, metamorphosis, diapause

Head

six segments, mandibles, labrum, maxillae

Thorax

three segments, prothorax, mesothorax, metathorax

Abdomen

holds guts/reproductive organs

Wing anatomy

forewing, hindwing

Entomophobia

fear of insects because they invade our homes, evade capture, threaten individuality, reproduce quickly, otherness, defy our will, harm us

Drivers of insect decline

intensive agriculture because they lose sources of food and shelter, pesticides because it affects their reproduction and development

Insecticide

Nicotine, extracted from the plant Nicotiana tabacum, has been used for hundreds of years to kill insects. Affects the central nervous system of the target animal directly

Pests

carpet beetle - larvae ingest keratin (fibrous animal product), live indoor in dark, undisturbed places, manage them by cleaning and storing susceptible goods at cold temps

Top targets of insecticides

acetylcholinesterase, voltage-gated sodium channel, acetylcholine receptor, and GABA receptor (all apart of the nervous system)

How does nicotine work?

binds to ACh receptor, acts as an agonist (hyper activation), which leads to muscular contraction, paralysis, and death

What kind of approach is IPM?

holistic/knowledge based, very individualized

What do you need to know for IPM?

data on crop/pests, growing season, climate change, cultural practices

Economic threshold

density at which control is implemented, affected by costs, market price, and pest population growth rate

Limits on insect size

tracheal system, spiracles, oxygen concentration in atmosphere, circulatory system, exoskeleton, CNS

Toxin

harmful substance produced by an organism

Venom

toxin injected into an organism through a bite or sting

Poison

harmful substances, regardless of origin

Envenomation

act or passage of poisoning by venom

Types of venom

neurotoxic, cytolytic, hemolytic, hemorrhagic, blistering

Spiders

don’t have antennae, simple eyes, 2 magmata, 2 pairs of modified mouthparts

Scorpions

evolved pedipalps, neurotoxic venom, indirect fertilization

Subsocial

some degrees of parental care

Communal

females use the same nest without cooperation in brood care

Quasisocial

same nest and cooperative brood care

Semisocial

quasisocial plus division of labor

Eusocial

semisocial plus overlap in generations and offspring assist insects (reproductive division of labor)

Constriction

key adaptation in the evolution of socially in Hymenoptera because stringers are used to protect colonies, self-sacrifice

Why did eusociality likely evolve?

high relatedness (genetic hypothesis) or high benefit-to-cost ratio (ecological hypothesis)

Haplodiploid

all males are haploid, females are diploid, sons are unfertilized eggs, daughters are fertilized eggs

Murder hornets

eusocial, also known as northern giant hornet

Necrophages

decomposers, diptera, coleoptera

Parasites and predators

diptera, Coleoptera, wasps

Blow flies (Calliphoridae)

most important for forensic entomology, first arrivals to body, 3 larval instars that last 1-2 weeks

Flesh flies

Sarcophagidae, arrive early, carrion feeders and predators

What size flies should you use to estimate PMI?

largest blow flies

Horizontal transmission

virus comes from animal, transmitted to mosquito, transmitted to human

Vertical transmission

passage of virus between different generations of mosquitoes through eggs

Venereal transmission

transmission of virus from male infected mosquito to female mosquito during copulation

Nonviremic transmission

transmission of virus between cofeeding mosquitoes

mosquitoes family

Culicidae

cockroaches order

Blattodea

black flies family

Simuliidae

horse and deer flies’ family

Tabanidae

house flies, stable flies, and horn flies’ family

Muscidae

Pathogen

microorganism that can cause disease

Parasite definition

an organism that lives in/on host

Mortality definition

number of deaths in a population, often expressed as a rate over a specific time period

Morbidity definition

state of being diseased or having a disease, illness, or medical condition, as opposed to death

Prevalence definition

number of existing cases

Incidence definition

number of new cases/period of time

Endemic definition

disease that is restricted to a specific geographic area

Epidemic definition

rapid spread of disease to a large number of hosts in a given population within a short period of time

Pandemic definition

an epidemic occurring worldwide, affecting a large number of people

Ways to differentiate between butterflies and moths

moths have feathery antenna while butterflies have thicken club antenna, moths are duller color-wise

What is a phylogeny?

a hypothesis about evolution

Root on phylogenetic tree

most recent common ancestor

Nodes on phylogenetic tree

ancestors

Branches on phylogenetic tree

long parts of the tree that represent evolutionary lineages

Leaves on phylogenetic tree

species at the tips of the branches

Polytomy on phylogenetic tree

a branch point with more than two descendant taxa, indicating uncertain evolutionary relationships

What causes separation on phylogenetic tree?

isolation and time

Arbovirus definition

large group of RNA viruses spread mainly by blood sucking insects

Epidemiology definiton

study of distribution, determinants, and control of diseases and other health-related events in populations

Species of mosquitoes to know

Anopheles gambiae, Aedes aegypti

Red imported fire ant

introduced to Alabama last century from South America and spread across southern USA since, they can kill young trees and injure animals and people. Their large nests located in fields damage equipment during harvesting. They can move to non-infested areas by hitchhiking on agricultural commodities, can sting repeatedly

Aedes aegypti

primarily bites humans, spreads yellow fever, dengue, and Zika, container breeders

Malaria

influenced agriculture, settlement, reinforced class/gender inequities, led to creation of CDC. Transmitted primarily from female Anopheles gambiae bite, treated with antimalarial medications. Most common in tropical regions of the world, particularly in sub-Saharan Africa. Led to medical developments (discovery of Quinine as cure)

Civil war

malaria prevented the Union army from taking Richmond in 1861. The confederates did not have to deploy many of their troops because so many members of the Union army were sick.

Napoleon trying to reach India

had to travel through Russia, before reaching Russia, Napoleon wouldn’t let his army touch their rations in Poland. Russians just kept retreating in Russia and refused to engage because lice spread typhus to Napoleon’s army. Lost 400,000 soldiers, with more than half dying from disease

Anopheles gambiae

vectors malaria, breed in larger bodies of water

Screwworm fly

direct damage includes blood loss, inflammation/itching, allergic responses, indirect damage includes vectors of pathogens. In the family Calliphoridae (blow flies)

Sterile insect technique

female screwworms only mate once (males mate many times), so sterile males mate with females os that the eggs the female lays are unfertilized. Sterilized using radiation

What makes up the human footprint?

built environments, population density, electric infrastructure, crop lands, pasture lands, roads, railways, and navigable waterways

How does human footprint affect VBDs?

man-made water sources can serve as breeding grounds for anopheles gambiae

What is the extrinsic incubation period?

the time interval between when a vector ingests an infectious blood meal and becomes capable of transmitting the pathogen to a new host, decreases in warmer temps

Biological communities

assemblages of communities or discrete interactions

When do blow flies/flesh flies dominate?

early stages of decomposition

When is diversity highest in decay stages?

in the middle stages (bloated/decay)

Challenges that aquatic insects face in freshwater

low O2, buoyancy, locomotion, acquisition of food/resources, reproduction, metamorphosis, salt/water balance