Laboratory acclimation to autumn-like conditions induces freeze tolerance in the spring field cricket Gryllus veletis (Orthoptera: Gryllidae)

2019 ◽

Vol 286 (1899) ◽

pp. 20190050 ◽

Cited By ~ 8

Author(s):

Jantina Toxopeus ◽

Vladimír Koštál ◽

Brent J. Sinclair

Keyword(s):

Fat Body ◽

Ex Vivo ◽

Freeze Tolerance ◽

Field Cricket ◽

Ice Formation ◽

Low Molecular Weight ◽

Manipulative Experiments ◽

Gryllus Veletis ◽

Freeze Tolerant

Freeze tolerance, the ability to survive internal ice formation, facilitates survival of some insects in cold habitats. Low-molecular-weight cryoprotectants such as sugars, polyols and amino acids are hypothesized to facilitate freeze tolerance, but their in vivo function is poorly understood. Here, we use a combination of metabolomics and manipulative experiments in vivo and ex vivo to examine the function of multiple cryoprotectants in the spring field cricket Gryllus veletis . Cold-acclimated G. veletis are freeze-tolerant and accumulate myo -inositol, proline and trehalose in their haemolymph and fat body. Injecting freeze-tolerant crickets with proline and trehalose increases survival of freezing to lower temperatures or for longer times. Similarly, exogenous myo -inositol and trehalose increase ex vivo freezing survival of fat body cells from freeze-tolerant crickets. No cryoprotectant (alone or in combination) is sufficient to confer freeze tolerance on non-acclimated, freeze-intolerant G. veletis . Given that each cryoprotectant differentially impacts survival in the frozen state, we conclude that small cryoprotectants are not interchangeable and likely function non-colligatively in insect freeze tolerance. Our study is the first to experimentally demonstrate the importance of non-colligative cryoprotectant function for insect freeze tolerance both in vivo and ex vivo , with implications for choosing new molecules for cryopreservation.

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Balancing Selection on Electrophoretic Variation of Phosphoglucose Isomerase in Two Species of Field Cricket: Gryllus veletis and G. pennsylvanicus

Genetics ◽

10.1093/genetics/147.2.609 ◽

1997 ◽

Vol 147 (2) ◽

pp. 609-621

Author(s):

Laura A Katz ◽

Richard G Harrison

Keyword(s):

Balancing Selection ◽

Emergent Property ◽

Phosphoglucose Isomerase ◽

Field Cricket ◽

Nucleotide Variation ◽

Eastern United States ◽

Electrophoretic Variation ◽

Sympatric Populations ◽

Field Crickets ◽

Gryllus Veletis

Two species of crickets, Gryllus veletis and G. pennsylvanicus, share six electrophoretic mobility classes for the enzyme phosphoglucose isomerase (PGI), despite evidence from other genetic markers that the two species are not closely related within eastern North American field crickets. Moreover, the frequencies of the two most common PGI electrophoretic classes (PGI-100 and PGI-65) covary in sympatric populations of these species in the eastern United States, suggesting that PGI may be subject to trans-specific balancing selection. To determine the molecular basis of the electrophoretic variation, we characterized the DNA sequence of the Pgi gene from 29 crickets (15 G. veletis and 14 G. pennsylvanicus). Amino acid substitutions that distinguish the electrophoretic classes are not the same in the two species, and there is no evidence that specific replacement substitutions represent trans-specific polymorphism. In particular, the amino acids that diagnose the PGI-65 allele relative to the PGI-100 allele differ both between G. veletis and G. pennsylvanicus and within G. pennsylvanicus. The heterogeneity among electrophoretic classes that covary in sympatric populations coupled with analysis of patterns of nucleotide variation suggest that Pgi is not evolving neutrally. Instead, the data are consistent with balancing selection operating on an emergent property of the PGI protein.

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The Effects of Dietary Nutrient Balance on Life-History Traits and Sexual Selection in the Field Cricket, Gryllus Veletis

10.22215/etd/2018-13279 ◽

2018 ◽

Author(s):

Sarah Harrison

Keyword(s):

Sexual Selection ◽

Life History ◽

Life History Traits ◽

Nutrient Balance ◽

Field Cricket ◽

Dietary Nutrient ◽

Gryllus Veletis

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Metabolic cost of freeze-thaw and source of CO2 production in the freeze-tolerant cricket Gryllus veletis

Journal of Experimental Biology ◽

10.1242/jeb.234419 ◽

2020 ◽

pp. jeb.234419

Author(s):

Adam Smith ◽

Kurtis F. Turnbull ◽

Julian H. Moulton ◽

Brent J. Sinclair

Keyword(s):

Metabolic Rate ◽

Metabolic Cost ◽

Field Cricket ◽

Co2 Production ◽

System Response ◽

Freezing And Thawing ◽

Freeze Thaw ◽

Metabolic Costs ◽

Gryllus Veletis ◽

Freeze Tolerant

Freeze-tolerant insects can survive the conversion of a substantial portion of their body water to ice. While the process of freezing induces active responses from some organisms, these responses appear absent from freeze-tolerant insects. Recovery from freezing likely requires energy expenditure to repair tissues and re-establish homeostasis, which should be evident as elevations in metabolic rate after thaw. We measured carbon dioxide (CO2) production in the spring field cricket (Gryllus veletis) as a proxy for metabolic rate during cooling, freezing and thawing and compared the metabolic costs associated with recovery from freezing and chilling. We hypothesized that freezing does not induce active responses, but that recovery from freeze-thaw is metabolically costly. We observed a burst of CO2 release at the onset of freezing in all crickets that froze, including those killed by either cyanide or an insecticide (thiacloprid), implying that the source of this CO2 was neither aerobic metabolism or a coordinated nervous system response. These results suggest that freezing does not induce active responses from G. veletis, but may liberate buffered CO2 from hemolymph. There was a transient ‘overshoot’ in CO2 release during the first hour of recovery, and elevated metabolic rates at 24, 48 and 72 hours, in crickets that had been frozen compared to crickets that had been chilled (but not frozen). Thus, recovery from freeze-thaw and the repair of freeze-induced damage appears metabolically costly in G. veletis, and this cost persists for several days after thawing.

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The calling songs of male spring field crickets (Gryllus veletis) change as males age

Behaviour ◽

10.1163/000579511x588812 ◽

2011 ◽

Vol 148 (9-10) ◽

pp. 1045-1065 ◽

Cited By ~ 10

Author(s):

Susan M. Bertram ◽

Lauren P. Fitzsimmons

Keyword(s):

Longitudinal Study ◽

Female Preference ◽

Field Cricket ◽

Mate Attraction ◽

Call Structure ◽

Field Crickets ◽

Sexual Traits ◽

Gryllus Veletis ◽

The Relationship ◽

Older Males

AbstractSexual traits are typically thought to convey information about a male's quality or condition. Female preference for older males has been documented in many taxa, but the evidence that males signal their age is inconclusive. We investigated lifetime patterns of acoustic mate attraction signalling in a longitudinal study of the spring field cricket, Gryllus veletis. We recorded males continuously throughout their lives, such that every pulse of sound produced by every male was analyzed. Our study answers two main questions: (1) Do calls change as males age? Our results reveal that the calls of male spring field crickets change with age; the calls of older males were quieter, with more silent periods within and between chirps, and produced less often than those of younger males. As males aged most of the changes in call structure reflect decreased calling effort. (2) What is the relationship between calling effort and longevity? Lifetime calling effort was positively related to longevity, such that males that called the most over their life also lived longer than males that called less. Together, our findings provide the most thorough exploration of lifetime signalling patterns in crickets to date.

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