which approximately 900 species have been identified. Some genera of the tarantulas hunt prey primarily in trees and other genera hunt on or near the ground. All tarantulas can produce silk; while arboreal species will typically reside in a silken "tube tent", terrestrial species will line their burrows with silk to stabilize the burrow wall and facilitate climbing up and down. Tarantulas mainly eat insects and other arthropods, using ambush as their primary method of prey capture. The biggest tarantulas can kill animals as large as lizards, mice, and birds. Tarantulas are found in tropical and desert regions around the world. Most tarantulas are harmless to humans, and some species are popular in the exotic pet trade. Some species, while not known to have ever produced human fatalities, have venom that can produce extreme discomfort over a period of several days.
[online] (http://www.springerlink.com.ezproxy.tlu.ee/content/lp454782714r0715/) Hughes, C. L., Kaufman, T. C. 2002. Hox genes and the evolution of the arthropod body plan. 4, 6. 459-499. [online] (http://ehis.ebscohost.com.ezproxy.tlu.ee/ehost/pdfviewer/pdfviewer?sid=7c738895-1958- 42d8-822f-d5386559d587%40sessionmgr14&vid=2&hid=3) (07.03.2012) Mayer, G., Harzsch, S. 2007. Immunolocalization of serotonin in Onychophora argues against segmental ganglia being an ancestral feature of arthropods. 7, 1, 118. [online] (http://www.springerlink.com.ezproxy.tlu.ee/content/y02u8xn8w5q15065/fulltext.html) (07.03.2012) Mayer, G., Whitington, P. M., Sunnucks, P., Pflüger, H-J. 2010. A revision of brain composition in Onychophora (velvet worms) suggests that the tritocerebrum evolved in arthropods. BMC Evolutionary Biology. 10, 255. [online] (http://www.springerlink.com.ezproxy.tlu.ee/content/8hq7711416578526/fulltext.pdf) (26.03.2012) Whitington, P. M., Mayer, G. 2011
annaabi.ee 
