Insects specimens

Many other insects are occasional casual invaders the ones described are merely those most commonly seen. Ordinarily, when one or two specimens of an insect species invade a clean bakery, nothing is seen of them until they have bred and developed into a definite focus of subsequent infection in other words, until there is a colony in the place where the original invader sought harborage. It has been common practice to seek out the colonies visually and spray them with a contact spray. This contact spray killed the adults and larva which it touched, but all too often left eggs and pupae to develop unharmed. 

Standardized techniques and equipment for such investigations are in widespread use. Unfortunately, the same cannot be said for metabolism investigations in aquatic animals. Most of the world s animals exclusive of the insects —over 200,000 known species -- live at least a part of their lives in water over 100 species have major economic importance and they form the populations most often at risk of exposure to a growing number of chemical pollutants, but science remains largely ignorant of the disposition of xenobiotics by intact, living specimens of even the most common of the aquatic animals. 

The next day was March 13. The camp in the forest, the hallowed-seeming spot where the transforming experiment had occurred, was dismantled. All the artifacts that set it apart from dozens of other Witoto huts were tucked away, and it was returned to its native anonymity. Outside, in a pile, we left quite a cargo trove behind us, for our forced evacuation by airplane left precious little room for any gear some insect and plant specimens would leave with us, the cameras, the notebooks on the experiment—that was it. The things that we left would be swiftly assimilated by the tolerant Witotos who owned the site of our attempted probe of hyper-space. 

Sir Joseph Banks, 1743-1820. English naturalist and collector of plants and insects President of the Royal Society from 1778-1820. His collections of books and natural history specimens were bequeathed to the British Museum. Lady Banks used to assist him m giving frequent receptions for the scientists... 

The seasonal variation in thermal hysteresis found in D. canadensis is due to more than shifts in concentrations of THPs, however. Unlike the freezing-avoidance strategy of Antarctic and Arctic fishes, in which the amount of thermal hysteresis appears to be due strictly to the concentration of THPs in the body fluids, freeze-avoiding insects employ a complex set of mechanisms to achieve the high levels of thermal hysteresis found for hemolymph in winter-collected specimens. 

Amber is soft, has a low melting point, and a very low density. Most amber will float in saturated salt water. It may be transparent, translucent or opaque, and varies in color. Most often it is yellow or brown, but specimens of red, blue, and green are known. Inclusions of insects, plant parts, dust, and other debris are sometimes found in amber formed from resin that was extruded onto the outside of a plant. There is lots of amber, however, that formed on the inside of plants, and this material rarely carries inclusions. Amber is very important to paleontologists because it preserves organisms, both plant and animal, that are far too delicate to be preserved by the normal fossilization processes of burial and dehydration. 

Insects are of interest as specimens in collections, but also as pests and agents of deterioration in collections of all kinds. They also contribute body parts, like wings, and chemicals to the manufacture of objects and materials found in collections. 

There are different standards of practice for collections of each type of animal. Insects are mostly preserved dry, pinned in specialized trays or boxes. Certain types of insects, like spiders or sometimes the larger beetles, may be fluid preserved in a standard 70% ethanol and water solution. Older collections sometimes include wet-preserved specimens in glycerin, oil, or formalin. 

During skinning, various compounds may be introduced into the specimen for the purposes of dissolving fats (acetone, gasoline, or other solvents), drying fat and tissue (borax, salt, cornmeal, diatomite, or plaster), and to kill insects (arsenic trioxide or borax). 

If preparation of an animal is done too quickly or without proper care, some natural compounds may remain in the specimen. Even though these compounds were liquid when the animal was alive, they may still be toxic. These include venom in the fangs of insects, snakes, some mollusks, and gila monsters. Mollusk shells in a dry collection may contain toxin if the body of the animal was not removed, but rather left to dessicate inside. 

The best way to ship material is live. Insects Drosophila, in particular) can be sent on small amounts of food in vials. Most marine organisms can be shipped live in sealed plastic bags. On receipt of the organisms, however, prompt treatment of the shipment is required. Specimens obtained for rearing should be placed in proper rearing media. Specimens obtained for protein or DNA extraction should be immediately and rapidly frozen at or below —70°. Frozen tissue should be shipped on dry ice. A much more convenient way to send tissue, however, is in 70-95% ethanol. The DNA yield and quality from specimens sent in ethanol are usually almost as good as from fresh or frozen tissue. Sperm can be shipped on wet ice if it is collected dry (i.e., undiluted in water) and if sodium azide is added to a final concentration of 0.01 -0.02% in order to prevent bacterial growth.13... 

The vast majority of invertebrate specimens are in ethanol. With the notable exceptions of insects, corals, some sponges, echinoids, asteroids,... 

Voucher specimens must be prepared, so save enough of the specimens, being certain they contain diagnostic features for positive identification. Vouchers should be deposited in established herbaria if they warrant it. Most herbaria probably would not have space for or desire large numbers of specimens of a single species from one locality or specimens lacking diagnostic characters. We feel it is desirable to keep vouchers for a number of years in case questions should arise about published work. Voucher specimens should be kept dry and insect-free in a special herbarium cabinet, preferably in a herbarium and perhaps at the home institution or in the care of the researcher if they are not appropriate for the herbarium. 

For fungi and some algae fresh field-collected specimens often are a source of insects and mites. Not only can these arthropods destroy specimens, but they can also destroy a culture collection by contamination as they move from one tightly sealed culture to the next. Mites also are suspected vectors in horizontal gene transfer between Drosophila spp.,25 and perhaps this form of contamination may be detected in fungi and algae one day. 

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