Parasitology Lec 1: Introduction to Invertebrates

what is an invertebrate

any animal lacking a backbone, including all species not classified as vertebrates

is invertebrate an official taxonomic group?

no

how many phyla does it include

30

more than what percent of all known animal species are invertebrates

98

invertebrates are the ____ group of animals in most environments

dominant

how many species of invertes have been named

1,305,075

what is the Linnaean shortfall

scientists have now described and named over 1.4 million species of organisms

this, however, represents _____ of the total species thought to occur on the earth

only a fraction

it has been estimated that there are between ____ species

10 and 30 million

often the new species that are discovered are so unique that they become

the sole representative of a new family, order or even phyla

most of the newly discovered species will be

invertebrates

while a great majority of the undiscovered animals are thought to be invertebrates, only what percent of today’s taxonomists specialize in these groups

30%

invertebrates are _____ to ecosystems

extremely important (example: grasslands)

*what is the major aboveground consumer of vegetation in grassland systems

*grasshoppers

*what is the major belowground consumer of vegetation in grassland systems

*nematodes

*there are ___ species of nematodes that are plant parasites

*2,500

it is estimated that how much of the world’s crop production is lost due to plant nematodes and most of this damage is caused by _____ nematodes

10%; root knot nematodes

certain invertebrates are used as what for controlling various agricultural pests

biological control agents (substitutes for insecticides)

give an example of the bio control agents

nematode parasites of insects are now available commercially for several horticultural and agricultural applications

these come in what form

gels and water-dispersible granules

they have been particularly effective against what

bark beetles and grasshoppers

The apple, almond, and 90 other crops in the U.S. depend on what for pollination

honeybees

these crops account for how much in annual sales

15 billion dollars

*are honeybees native to the U.S.?

*no, they have been imported

describe the colony collapse disorder

hundreds of thousands of honeybees abandon their hives and disappear. this is partly caused by another invertebrate, the Varroa mite

bumblebees, which are native to the U.S., pollinate how much of commercial crops in the U.S. and are also experiencing a serious decline

15%

invertebrates are used to what in aquatic habitats

evaluate and monitor pollutant stress

__insects are especially important

aquatic

what are used extensively in ohio

mussels

what are also increasing in importance

oligochaetes

what are used widely to monitor sewage effluent for toxicity

Cladocerans (Crustacea)

Biodiversity studies indicate that invertebrates are ___ in certain terrestrial and aquatic environments

rapidly being lost

this is due to what and give some examples

due to loss of habitat, pollution, etc. Ohio examples: Blue Kraner, Hine’s emerald dragonfly (which has become extinct now in ohio)

invert parasites of humans and domesticated animals: recent summaries of the worldwide prevalence of selected diseases show that there are more than enough existing infections for every living person to have

one

*know! what is a non-taxonmic, but often used term, which refers to the parasitic worms (name the 3)

Helminths, the 3 names for parasitic Helminths are flat worms, flukes, and roundworms

in 2003, the estimated global prevalence was how much for Ascaris lumbricoides (an intestinal roundworm), how much for Trichuris trichuura (human whipworm), and how much for human hookworm

26%, 17%, 15%

*These percentages have remained ____ for 50 years despite the fact that the earth’s population had more than doubled in that period

*virtually unchanged