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What are Collembola, and why the heck do we care?. Primitive, wingless, non-insect HexapodsLeaf litter decomposersDiets composed of fungi and algae*. *Verhoef et al., 1988. Components of winter ecology we have seen. Adaptations to coldEvidence of biotic soil activityBelow-snow temperatures that support lifeThe Antarctic is cold .
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1. Winter adaptations of the leaf litter and soil arthropod Collembola OR: Are these guys living amongst us?
Jeff McClenahan
March, 2006
3. Components of winter ecology we have seen Adaptations to cold
Evidence of biotic soil activity
Below-snow temperatures that support life
The Antarctic is cold
4. Winter active species Ceratophsella sigillata* Temperature dependent dormancy during summer
Main growing season is winter
Uses antifreeze molecules in algae: polyols
5. Glycerol production in Gomphiocephalus hodgsoni* Produced via hydrolysis of triaclglycerols
Able to enter the glycolytic pathway with help of ATP
High concentration in October and lower in January (Antarctic)
Measured super cooling point (SCP) as low as -38 degrees C
6. Partial desiccation in Onychiurus articus* Long periods of -2.5 degrees C, resulting in reduced water content
Lowered SCP from -6.1 to -15.5 degrees C
Gained normal body weight within 24 hours when water was available
7. Brief look at the process of ecdysis
8. Unexpected role of ecdysis in Tullbergia antarctica* Ametabolous ecdysis: sheds cuticle throughout life, even after adulthood
Sheds cuticle as a means to rid themselves of ice
9. What does this all mean? Arthropods where we dont expect them?
9000 named species
Inhabit high elevations and high latitudes
Evidence suggests that these winter systems are dynamic
Alpine tundra?
Sub-alpine forests?
10. Cited references Sinclair BJ and Sjursen H. 2001. Cold tolerance of the Antarctic springtail Gomphiocephalus hodgsoni. Antarctic Science 13:271-279
Worland MR. 1996. The relationship between water content and cold tolerance in the arctic collembolan Onychiurus arcticus. European Journal of Entomology 93:341-348
Worland MR. 2004. Factors that influence freezing in the sub-Antarctic springtail Tullbergia antarctica. Journal of Insect Physiology 51:881-894
Verhoef HA, Prast JE, Verweij RA. 1988. Relative importance of Fungi and Algae in the diet and nitrogen nutrition of Orchesella cincta and Tomocerus minor. Functional Ecology 2:195-201
Zettel J. 2000. Alpine Collembola-adaptations and strategies for survival in harsh conditions. Zoology-Analysis of Complex Systems 102:73-89