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Lab Manual
Natural History Event Species List


Sources: PowerPoint 01b , Web

1. Never handle venomous species and never place your hands or feet anywhere you can't see.

2. Venomous species are able to inject toxins into their victim (e.g., by teeth, stinger, fangs, etc.). Rattlesnakes and wasps are examples. Poisonous species produce toxins that may or may not be able to be injected. In this class, if I use the term "poisonous" I will be referring to non-venomous species that secrete toxins within their body or onto their skin. For example, the Sonoran Desert Toad is poisonous; you would never want to eat one but you don't have to worry about one attacking you. A rattlesnake is venomous, you can eat them, but never let them bite you.

3. Bark scorpion, black widow, brown spider, gila monster (debatable), coral snake, and rattlesnakes.

4. Hemolytic toxins: affect the circulatory system by destroying blood cells and vessels ("hemo" means blood). Symptoms include severe pain, swelling, discoloration, and local tissue death. Shock can occur. Example: most rattlesnakes. Neurotoxins: affect the nervous system ("neuro"). Symptoms may include local pain, headache, lethargy, facial paralysis and occasionally death by circulatory arrest or respiratory paralysis. Usually no swelling, discoloration, or tissue death. Examples include Black Widow, Scorpions, and Coral Snake. Other toxins include the protein-destroying toxins of brown spiders and the pain-causing toxins of gila monsters.

5. Food digestion, Subduing prey (so as to reduce the chance of injury in the process), and Defending against predators and other potential threats.

6. First, they have to have special equipment (venom glands, fangs, etc.). Second, venom is expensive to produce (materials and energy).

7. When used to subdue prey, they match the amount of venom to the prey type and size; for example, more venom is used when the prey size is larger or the prey can get away easier (e.g., birds). They try to avoid having to use venom defensively by using cryptic coloration (camouflage to avoid being seen in the first place), by using aposematic coloration or other warnings that they are dangerous, and/or by retreating.

8. Cryptic coloration is coloration that makes it difficult to see the animal (camouflage). Aposematic coloration is warning coloration that usually is bright, bold, and memorable (e.g., the orange and black of wasps). Note that some venomous species are cryptically colored (rattlesnakes), and some are aposematically colored (coral snakes).

9. Species that only pretend to be dangerous or inedible. Thus they receive the value of defense without the expense.

10. Nocturnal means active at night, diurnal means active during daylight, and crepuscular means active during the early morning and early evening periods.

11. Bark scorpion. Identified by having long, thin pincers.

12. Black widows: females are dangerous and can be identified by black body containing an hourglass shaped marking on the bottom side of the large abdomen. Brown spiders: identified by "spindly" appearance and violin-shaped marking on top of "head."

13. Two species: Gila Monster and Mexican Beaded Lizard.

14. Diurnal, mostly in spring when hunting young mammals and birds

15. Red and yellow kill a fellow, red and black friend of Jack. Coral snakes are red, yellow (or white), and black. The red and yellow bands touch each other. Also the bands go all the way around coral snakes. Batesian mimics either do not have red touching yellow or do not have bands going all the way around.

16. The number of times it has shed its skin (if no segments have been lost). Because they can shed their skin a variable number of times each year (depends on amount of food consumed, etc.), you cannot tell their age.

17. None, they give birth to live young.

18. Eyes (vision), nostrils (smelling), body (ground vibrations - similar to hearing), Pit Organ (senses heat), Jacobson's Organ (senses chemicals brought to it by the tongue to augment smell). The tongue mostly serves to collect the chemicals scents from the ground and air and to deliver the chemicals to the Jacobson's Organ on the roof of the mouth to give stereoscopic smell.