It's a (Really) Small World
Insects push the boundaries of smallness. Midnight movies to the contrary, there's only so large an exoskeleton-based creature can grow — theoretically, around 4-5 ounces (125-150 grams) [source: Meyer]. The largest living insect, the cricket-like New Zealand giant wētā, or wētāpunga, weighs about half that (but still outweighs a mouse or a sparrow!) [sources: NZDoC, The Telegraph [UK]].
One the smaller end of the scale, insects are wonders of miniaturization. Shakespeare's Hamlet spoke figuratively when he said, "I could be bounded in a nutshell, and count myself a king of infinite space." But some ant species establish entire colonies inside of acorns [sources: CISEO; Meyer]. Moreover, the smallest insects, such as the Costa Rican wasp Dichomorpha echmepterygis, can reach sizes smaller than some paramecium (single-celled protozoa) — 0.00055 inch or 0.139 millimeters. The majority of insects fall into the 0.1-1.0 inch (2-20 millimeter) range [source: Meyer].
Tiny creatures enjoy several advantages. They need only the tiniest morsel or drop to sustain their bodily needs, hide from predators in nearly any setting and find shelter and shade wherever they might be. To them, a pebble is a boulder and a tiny crack, a fissure. You might say that, for insects, the world is incredibly small and therefore unspeakably vast.
Author's Note: 10 Traits That Make Insects Survivors
It's so very easy to get lost in the small yet vast universe of insects. With so many species and so varied a range of adaptations, you just want to read on and on, or to shrink yourself down and experience just for a moment what their splendid and multifarious universe must be like.
More Great Links
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- Carter, J. Stein. "Coevolution and Pollination." University of Cincinnati Clermont College. March 29, 2005. (May 1, 2015) http://biology.clc.uc.edu/courses/bio303/coevolution.htm
- Center for Insect Science Education Outreach. "Ant Information." University of Arizona. 1997. (May 4, 2015) http://insected.arizona.edu/antinfo.htm
- Choi, Charles. "Fact or Fiction?: A Cockroach Can Live Without Its Head." Scientific American. March 15, 2007. (May 6, 2015) http://www.scientificamerican.com/article/fact-or-fiction-cockroach-can-live-without-head/
- Danforth, Bryan. "Insect Diversity." Cornell University Department of Entomology. (May 4, 2015) https://courses.cit.cornell.edu/ent201/diversity.html
- Danforth, Bryan. "Handout — Insect Orders and the Timeline of Insect Evolution." Cornell University Department of Entomology. (May 4, 2015) https://courses.cit.cornell.edu/ent201/content/diversity.pdf
- Encyclopedia Britannica. "Exoskeleton." Children's Encyclopedia. (May 8, 2015) http://kids.britannica.com/elementary/article-399448/exoskeleton
- Fleury, Bruce E. "Arthropods." Tulane University Department of Ecology and Evolutionary Biology. (May 4, 2015) http://www.tulane.edu/~bfleury/diversity/labguide/arthropod.html
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- Meyer, John R. "A Class of Distinction: Reasons for Success." North Carolina State University Department of Entomology. Jan. 21, 2007. (May 1, 2015) http://www.cals.ncsu.edu/course/ent425/text01/success.html
- Meyer, John R. "Social Insects." North Carolina State University Department of Entomology. March 16, 2005. (April 27, 2015) http://www.cals.ncsu.edu/course/ent425/tutorial/Social/
- Misof, Bernhard, et al. "Phylogenomics Resolves the Timing and Pattern of Insect Evolution." Science. Vol. 346, no. 6210. Page 763. Nov. 7, 2014. (April 27, 2015) http://www.sciencemag.org/content/346/6210/763
- Mitchell, B. K. and J. S. Scott. "An Introduction to Insect Structure." Department of Biological Sciences, University of Alberta. (May 4, 2015) http://www.biology.ualberta.ca/mitchell.hp/Structure/modules.pdf
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- Mythbusters. "Cockroaches Survive Nuclear Explosion." From MythBusters: Airplane on a Conveyor Belt.Jan. 30, 2008. (May 6, 2015) http://www.discovery.com/tv-shows/mythbusters/mythbusters-database/cockroaches-survive-nuclear-explosion/
- New Zealand Department of Conservation. "Giant Wētā / Wētāpunga." (May 1, 2015) http://www.doc.govt.nz/nature/native-animals/invertebrates/weta/giant-weta-wetapunga/
- Smithsonian Institution. "Information Sheet Number 18: Numbers of Insects (Species and Individuals)." Department of Systematic Biology, Entomology Section, National Museum of Natural History. (May 4, 2015) http://www.si.edu/encyclopedia_si/nmnh/buginfo/bugnos.htm
- The Telegraph [UK]. "World's Biggest Insect is So Huge It Eats Carrots." Dec. 1, 2011. (May 1, 2015) http://www.telegraph.co.uk/news/earth/wildlife/8930070/Worlds-biggest-insect-is-so-huge-it-eats-carrots.html
- University of California, Berkeley. "Evolution 101. Understanding Evolution." (May 6, 2015) http://evolution.berkeley.edu/evolibrary/article/evo_01
- Wada-Katsumata, Ayako, Jules Silverman and Coby Schal. "Changes in Taste Neurons Support the Emergence of an Adaptive Behavior in Cockroaches." Science. Vol. 340, no. 6135. Page 972. May 24, 2013. (May 8, 2015) http://www.sciencemag.org/content/340/6135/972
- Whitman, Douglas W., and Anurag A. Agrawal. "What is Phenotypic Plasticity and Why is It Important." Phenotypic Plasticity of Insects. Vol. 10. Page 1. 2009 (May 8, 2015) http://www.eeb.cornell.edu/agrawal/pdfs/whitman-and-agrawal-2009-Ch_1-Phenotypic-Plasticity-of-Insects.pdf
- Wigglesworth, Vincent B. "Insect: Head." Encyclopedia Britannica. July 20, 2014. (May 4, 2015) http://www.britannica.com/EBchecked/topic/289001/insect/41285/Head
- Yeates, David. "Insects Are the Great Survivors in Evolution: New Study." The Conversation. Nov. 6 2014. (April 27, 2015) http://theconversation.com/insects-are-the-great-survivors-in-evolution-new-study-33786
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