Entomology (Study of Bugs)/this time a spider.


QUESTION: ok.. i don't  need a picture for this one. i identified it. but i was siting at my  computer here and out of the corner of my eye i see a little yellow spider walk by. now the first reaction anyone would have is to freak out, but i slowly grabbed the tube and trapped it (rest assure i will set it outside tomorrow). but before i trapped it and as i was reaches for the tube, it turned and started to run fast. now I've identified this as a long legged sac spider (definitely not a yellow sack spider). some searches say that are deadly venomous; others say it's only causes small discomfort and then itchy afterwards unless allergic.which is it? i have another  question. the harvestmen never run away from me; but the long legged sac spider did. could this be because the long legged sac spider has more intelligence then a harvestmen; or can they see better and are afraid of a much larger moving thing? or is it possible they have developed some sort of blueprint? thanks for your time and help. Take care and have a nice day.

ANSWER: The classification of sac spiders can be confusing. The Genus of the yellow sac spider and the longlegged sac spider is Cheiracanthum. Some  tThe  species of the yellow sac spider is C. inclusum. If I look for the classification of the Longlegged sac spider all I can find is Cheiracanthum spp
 Most spider experts consider sac spiders to b mildly venomous.
 As to the comparison between sac spiders and harvestmen: Harvestman re not usualy classfied as spiders. They have a single body segment and no venom.
 These invertebrates do not behave with any intelligence. Their behavior including speed is the results of their DNA.

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QUESTION: danke for your reply. but i'm not just talking about speed- that; no doubt is due to DNA.  but as i turned my head; it stopped as if to acknowledge i was their and when i reached for the tube, it turned and ran faster then it was walking on the wall. now some could say this is just the spider's instinct to run away from possible predator.. but could it be that the long-legged sac spider posses some what intelligence.. or does it see better? i am going to set it loose out back by the garage i  don't  use sense i read they like buildings. as for harvestmen; they don't run- they just mosey on over to where they want to go. my house is old; so i get allot of bugs in it and around it.

Spiders do have better vision then Harvestmen.  Harvestmen do not seem to have any way to protect themselves. They do have some protective coloration and can hide. But they are easy to pickup.
When we think about intelligence we usually base intelligent behavior on how an animal reacts to certain situations and if the behavior involves consciousness. Biologists do not assign consciousness to invertebrates. Intelligence requires a central nervous system

Entomology (Study of Bugs)

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Walter Hintz


I can answer any questions about insects and spiders.


I have taught science for over 57 years. I am presently teaching biology at the college level. I have done extensive graduate work in entomology.

Momentum Magazine The Ohio Journal of Science

B.S. In Ed Kent State Unuv M.Sc The Ohio State Univ National Science Foundation Fellowships: Electron Microscopy Univ of California Entomology Kent State Univ

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