Dimensional Parameters:
The 1985 measurements on the eight insculpta's showed the following pertaining to sexual dimorphism: Carapace length - males: 7 1/16 - 7 14/16 inches (17.8 - 19.9 centimeters). Carapace length - females: 6 11/16 - 7 4/16 inches (17.4 - 18.5 centimeters). All test subjects were mature adults and as such, males showed a larger ultimate size. Carapace width - males: 5 4/16- 5 12/16 inches (13.6 - 14.4 centimeters). Carapace width - females: 5 1/2 - 5 11/16 inches (13.9 - 14.4 centimeters). Again, males were slightly larger. Width of head - males: 1 3/16 - 1 7/16 inches (2.8 - 3.6 centimeters). Width of head - females: 1 1/16 - 1 3/16 inches (2.7 - 2.9 centimeters). Males show a significant difference. Carapace minus Plastron length (Carastron index) - Males: 6/16 - 15/16 inches ( 1.0 - 2.2 centimeters). Carapace minus Plastron length (Carastron index) - females: 5/16 - 2/16 inches ( 0.9- -0.3 centimeters). This was a sizeable difference with males possessing a large carapace overhang. In subsequent observations, this is always the case. Female redlegs phenotype insculpta have a narrower overhang but in the case of the yellowlegs phenotype insculpta, the plastron was actually longer than the carapace (giving a minus Carastron value). One yellowlegs female that had a Carastron value of -.06 (not included in parameter table) was unusual in having a completely round carapace similar to a dinner plate. One thought is that she was a member of a peripheral isolate population. Another thought was paedomorphism of the carapace. Hatchling Glyptemys insculpta display a round carapace which develops into a more oval shape during development towards adulthood.
Tinklepaugh Labyrinth Experiments:
Glyptemys insculpta indeed showed great resourcefulness and speed in problem solving. In addition to finding escape routes quickly, subjects in variation quickly found correct pathways to food and male Glyptemys insculpta to females in different sections of the labyrinth. Male insculpta had been observed in 1985 lying in ambush near pools for females to happen by looking to soak or a drink. The male would proceed to jump on the back of the female to mate. A three dimensional approach in the labyrinth experiments did not slow down the wood turtles in their quest. One male in particular was very adroit in climbing and would systematically probe for weaknessess. This was done at all levels in the outdoor fencing he was kept in.
Yerkes Space Reaction Experiments: At all levels up to twenty feet, great fear and respect of heights was demonstrated by Geochelone carbonaria. Glyptemys insculpta and Terrapene carolina carolina showed respect for all distances but did not show fear at the two foot height. Clemmys guttata showed respect and fear at ten and twenty feet, but did not so at two and five feet. Indeed, at the latter two heights, the subjects tried to drop off as aquatic species would be expected to into buoyant water.
Mirror Experiment:
All test species with the exception of Glyptemys insculpta, showed no interest in their reflected images. Glyptemys insculpta appeared more cognizant of it's own reflections when facing mirrors. test subjects would stop, lower their heads, and touch 'noses' with their reflections. This behavior has been noted between encounters between two Glyptemys insculpta. In addition to the head lowering and nose tipping, individuals will often tip their heads and sniff each other in the manner of dogs. They seem to treat each other on an individual basis. Knowlton describes the behavior of insculpta in an encounter in the following manner: "Their heads were slowly lowered when the turtles were with eight inches of each other. Next, their heads were swung from side to side for up to an hour without cessation. Mating occurred in a nearby pool. " Harding also mentions that Glyptemys insculpta conduct a mating dance initiated by both parties. They position themselves in front of one another and swing their heads in a sideways swing.
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