Invertebrates in Hot and Cold Arid Environments

ISBN-13: 9783642795855 / Angielski / Miękka / 2011 / 275 str.

Lauritz Somme

Opis

Comparisons are made of the adaptations of invertebrates from polar deserts with those of temperate and subtropical deserts. These regions represent some of the most hostile environments on earth and an array of strategies for survival has been developed. Polar species are well adapted to cold and experience arid conditions due to low precipitation and lack of liquid water during the winter. Similarly, temperate desert invertebrates are adapted to dry conditions and are also exposed to low winter temperatures.
Terrestrial arthropods maintain their water balance through behavioural and physiological adaptations. Tardigrades and nematodes are remarkable in their ability to lose all their water, enter a state of anhydrobiosis and be revived when moisture becomes available again.

Spis treści

1 The Climate of Arid Environments.- 1.1 Subtropical and Temperate Deserts.- 1.1.1 Definitions.- 1.1.2 The Distribution of Deserts.- 1.1.3 Microclimate.- 1.2 Polar Deserts.- 1.2.1 The Arctic.- 1.2.2 The Antarctic.- 1.2.3 Microclimate.- 1.3 The Limitation of Water in Antarctic Terrestrial Ecosystems.- 1.3.1 Latitudinal Variations.- 1.3.2 Microclimatic Variations.- 1.4 Conclusions.- 2 The Fauna of Hot and Cold Arid Deserts.- 2.1 The Diversity of Hot Desert Invertebrates.- 2.1.1 Introduction.- 2.1.2 Soil Fauna: Microarthropods and Nematodes.- 2.1.3 Ants and Termites.- 2.1.4 Herbivores.- 2.1.4 Detritivorous Macroarthropods.- 2.1.6 Necrophagous and Coprophagous Arthropods.- 2.1.7 Predaceous Arthropods.- 2.2 The Fauna of Polar Regions.- 2.2.1 Introduction.- 2.2.2 Nematodes.- 2.2.3 Tardigrades.- 2.2.4 Rotifers.- 2.2.5 Other Invertebrates.- 2.2.6 Terrestrial Arthropods.- 2.3 Comparison of Hot and Cold Arid Environments.- 3 Tolerance to Arid Conditions in Terrestrial Arthropods.- 3.1 Microarthropods.- 3.1.1 Alpine Species.- 3.1.2 Polar Species.- 3.2 Coleoptera.- 3.2.1 Alpine Species.- 3.2.2 Polar Species.- 3.2.3 Tropical and Temperate Lowland Species.- 3.3 Other Terrestrial Arthropods.- 3.3.1 From Lowland Deserts.- 3.3.2 Alpine Millipedes.- 3.4 Conclusions.- 4 The Physiology of Tolerance to Desiccation.- 4.1 Introduction.- 4.2 Evaporative Water Losses.- 4.2.1 Beetles.- 4.2.2 Scorpions.- 4.3 The Cuticula of Terrestrial Arthropods.- 4.3.1 Structure.- 4.3.2 Restriction of Water Loss.- 4.3.3 Cuticular Lipids.- 4.3.4 Desert Arthropods.- 4.3.5 Evaporative Cooling.- 4.4 Water Absorption.- 4.4.1 The Hindgut of Insects.- 4.4.2 The Cryptonephridial System.- 4.4.3 Water Absorption in Other Terrestrial Arthropods.- 4.5 Osmoregulation.- 4.5.1 Occurrence in Different Taxa.- 4.5.2 Desert Tenebrionids.- 4.5.3 Alpine Beetles.- 4.6 Conclusions.- 5 Anhydrobiosis in Terrestrial Invertebrates.- 5.1 Introduction.- 5.2 Nematodes.- 5.2.1 Tolerance to Desiccation.- 5.2.2 Rates of Dehydration.- 5.2.3 Nematodes from Hot Deserts.- 5.2.4 Antarctic Nematodes.- 5.2.5 Accumulation of Trehalose.- 5.3 Tardigrades.- 5.3.1 Tun Formation.- 5.3.2 Ecological Implications.- 5.3.3 Accumulation of Trehalose.- 5.3.4 Recovery from Anhydrobiosis.- 5.4 Rotifers.- 5.5 Terrestrial Arthropods.- 5.5.1 Collembola.- 5.5.2 Chironomid Midges.- 5.6 Biochemical Aspects of Anhydrobiosis.- 5.7 Conclusions.- 6 Behavioural Adaptations.- 6.1 Arthropods from Hot Deserts.- 6.1.1 Introduction.- 6.1.2 Burrowing.- 6.1.3 Circadian and Seasonal Rhythms.- 6.1.4 Thermoregulation.- 6.2 Polar and Alpine Terrestrial Arthropods.- 6.2.1 Introduction.- 6.2.2 Mating and Oviposition.- 6.2.3 Microarthropods.- 6.2.4 Behavioural Thermoregulation.- 6.2.5 Avoidance of Heat and Cold by Alpine Tropical Arthropods.- 7 Phenological Adaptations.- 7.1 Life Cycles.- 7.1.1 Hot Desert Invertebrates.- 7.1.2 Polar Species.- 7.1.3 Alpine Species.- 7.1.4 Conclusions.- 7.2 Diapause and Quiescence.- 7.2.1 Introduction.- 7.2.2 Principle Features of Diapause.- 7.2.3 Dormancy in Tropical Insects.- 7.2.4 Dormancy in Polar Species.- 7.2.5 Conclusions.- 8 Water Balance During Overwintering.- 8.1 Introduction.- 8.2 Choice of Overwintering Sites.- 8.2.1 Environmental Factors.- 8.2.2 Cues for Overwintering.- 8.2.3 Anaerobiosis.- 8.3 Moisture Content of Overwintering Sites.- 8.3.1 Lack of Fluid Water.- 8.3.2 Water Vapour Pressure in Frozen Habitats.- 8.3.3 Longevity and Saturation Deficit.- 8.4 Inoculative Freezing.- 8.4.1 Contact with Ice and Inoculation.- 8.4.2 Protection Against Inoculative Freezing.- 8.5 The Effect of Dehydration on Cold Hardiness.- 8.6 Conclusions.- 9 Cold Hardiness in Terrestrial Arthropods.- 9.1 Introduction.- 9.2 Concepts of Cold Hardiness.- 9.2.1 Definition of Important Concepts.- 9.3 Freeze Susceptible Species.- 9.3.1 The Importance of Supercooling.- 9.3.2 Supercooling Capacity in Microarthropods.- 9.3.3 Removal of Ice-Nucleating Agents.- 9.3.4 Seasonal Changes.- 9.3.5 Gut Content and Ice-Nucleating Agents.- 9.3.6 Low Molecular Weight Cryoprotectant Substances.- 9.3.7 Thermal Hysteresis Proteins.- 9.3.8 Cryoprotectants in Alpine and Polar Microarthropods.- 9.4 Freeze Tolerant Species.- 9.4.1 Why is Freezing Injurious?.- 9.4.2 The Occurence of Freeze Tolerance in Insects.- 9.4.3 Polar and alpine insects.- 9.4.4 Variations in the Degree of Freeze Tolerance.- 9.4.5 Ice Nucleation in Freeze Tolerant Species.- 9.4.6 Cryoprotectant Substances.- 9.5 Freeze Tolerance Versus Freeze Avoidance.- 10 Hot Desert Arthropods at Low Temperatures.- 10.1 Preadaptation to Cold.- 10.2 Cold Hardiness of Different Taxa.- 10.2.1 Scorpions.- 10.2.2 Centipedes.- 10.2.3 Spiders.- 10.2.4 Insects.- 10.3 Conclusions.- 11 Cold Tolerance in “Lower” Invertebrates.- 11.1 Nematodes.- 11.1.1 Strategies of Cold Hardiness.- 11.1.2 Antarctic Nematodes.- 11.1.3 Freeze Tolerance During Anhydrobiosis.- 11.1.4 Freeze Tolerance or Freeze Avoidance?.- 11.2 Tardigrades.- 11.2.1 Freezing in Liquid Gases.- 11.2.2 Freezing at Environmental Temperatures.- 11.2.3 Antarctic Tardigrades.- 11.3 Rotifers.- 11.4 Lumbricid Earthworms.- 11.4.1 Effect of Dehydration.- 11.4.2 Long Term Survival.- 11.4.3 A Protective Dehydration Mechanism.- 11.5 Conclusions.- 12 Summary and Concluding Remarks.- 12.1 Deserts.- 12.2 The Fauna.- 12.3 Behaviour.- 12.4 Life Cycles.- 12.5 Terrestrial Arthropods and Aridity.- 12.6 Cold Hardiness.- 12.6.1 Terrestrial Arthropods.- 12.6.2 Tardigrades and Nematodes.- 12.6.3 Lumbricid Earthworms.- 12.7 Combined Tolerance of Cold and Drought.- 12.8 Anhydrobiosis.- References.

O autorze

Deserts represent particularly hostile environments for their inhabitants. Lauritz Somme, Professor of Entomology at the University of Oslo, describes how spiders, insects and other invertebrates have adapted to these harsh conditions, focusing in particular on life in polar regions compared to that in temperate deserts.