Freeze tolerance in an arctic Alaska stonefly
Most aquatic insects do not survive subzero temperatures and, for those that do, the physiology has not been well characterized. Nemoura arctica is a species of stonefly widely distributed throughout arctic and subarctic Alaska. We collected nymphs from the headwaters of the Chandalar River, where w...
Published in: | Journal of Experimental Biology |
---|---|
Main Authors: | , , , |
Format: | Text |
Language: | English |
Published: |
Company of Biologists
2009
|
Subjects: | |
Online Access: | http://jeb.biologists.org/cgi/content/short/212/2/305 https://doi.org/10.1242/jeb.020701 |
id |
fthighwire:oai:open-archive.highwire.org:jexbio:212/2/305 |
---|---|
record_format |
openpolar |
spelling |
fthighwire:oai:open-archive.highwire.org:jexbio:212/2/305 2023-05-15T14:59:54+02:00 Freeze tolerance in an arctic Alaska stonefly Walters, Kent R. Sformo, Todd Barnes, Brian M. Duman, John G. 2009-01-15 00:00:00.0 text/html http://jeb.biologists.org/cgi/content/short/212/2/305 https://doi.org/10.1242/jeb.020701 en eng Company of Biologists http://jeb.biologists.org/cgi/content/short/212/2/305 http://dx.doi.org/10.1242/jeb.020701 Copyright (C) 2009, Company of Biologists Research Article TEXT 2009 fthighwire https://doi.org/10.1242/jeb.020701 2015-03-01T00:41:06Z Most aquatic insects do not survive subzero temperatures and, for those that do, the physiology has not been well characterized. Nemoura arctica is a species of stonefly widely distributed throughout arctic and subarctic Alaska. We collected nymphs from the headwaters of the Chandalar River, where we recorded streambed temperatures as low as –12.7°C in midwinter. When in contact with ice, autumn-collected N. arctica cool to –1.5±0.4°C before freezing, but individuals survived temperatures as low as –15°C, making this the first described species of freeze-tolerant stonefly. N. arctica clearly survive freezing in nature, as winter-collected nymphs encased in ice demonstrated high survivorship when thawed. In the laboratory, 87% of N. arctica nymphs frozen to –15°C for 2.5 weeks survived and, within one month of thawing, 95% of the last-instar nymphs emerged. N. arctica produce both glycerol and ice-binding factors (e.g. antifreeze protein) in response to low temperature. Hemolymph glycerol concentrations increased from 3 mmol l–1 to 930±114 mmol l–1 when temperatures were decreased from 4°C to –8°C, and N. arctica continued to produce glycerol even while frozen. Although the hemolymph of individual cold-acclimated nymphs occasionally exhibited more than a degree of thermal hysteresis, typically the hemolymph exhibited only hexagonal crystal growth, indicating a low concentration of ice-binding factor. Hemolymph of nymphs acclimated to subzero temperatures had recrystallization inhibition. These results demonstrate that, in the face of freezing conditions, N. arctica exhibit overwintering adaptations similar to those of terrestrial insects. Text Arctic Subarctic Alaska HighWire Press (Stanford University) Arctic Midwinter ENVELOPE(139.931,139.931,-66.690,-66.690) Journal of Experimental Biology 212 2 305 312 |
institution |
Open Polar |
collection |
HighWire Press (Stanford University) |
op_collection_id |
fthighwire |
language |
English |
topic |
Research Article |
spellingShingle |
Research Article Walters, Kent R. Sformo, Todd Barnes, Brian M. Duman, John G. Freeze tolerance in an arctic Alaska stonefly |
topic_facet |
Research Article |
description |
Most aquatic insects do not survive subzero temperatures and, for those that do, the physiology has not been well characterized. Nemoura arctica is a species of stonefly widely distributed throughout arctic and subarctic Alaska. We collected nymphs from the headwaters of the Chandalar River, where we recorded streambed temperatures as low as –12.7°C in midwinter. When in contact with ice, autumn-collected N. arctica cool to –1.5±0.4°C before freezing, but individuals survived temperatures as low as –15°C, making this the first described species of freeze-tolerant stonefly. N. arctica clearly survive freezing in nature, as winter-collected nymphs encased in ice demonstrated high survivorship when thawed. In the laboratory, 87% of N. arctica nymphs frozen to –15°C for 2.5 weeks survived and, within one month of thawing, 95% of the last-instar nymphs emerged. N. arctica produce both glycerol and ice-binding factors (e.g. antifreeze protein) in response to low temperature. Hemolymph glycerol concentrations increased from 3 mmol l–1 to 930±114 mmol l–1 when temperatures were decreased from 4°C to –8°C, and N. arctica continued to produce glycerol even while frozen. Although the hemolymph of individual cold-acclimated nymphs occasionally exhibited more than a degree of thermal hysteresis, typically the hemolymph exhibited only hexagonal crystal growth, indicating a low concentration of ice-binding factor. Hemolymph of nymphs acclimated to subzero temperatures had recrystallization inhibition. These results demonstrate that, in the face of freezing conditions, N. arctica exhibit overwintering adaptations similar to those of terrestrial insects. |
format |
Text |
author |
Walters, Kent R. Sformo, Todd Barnes, Brian M. Duman, John G. |
author_facet |
Walters, Kent R. Sformo, Todd Barnes, Brian M. Duman, John G. |
author_sort |
Walters, Kent R. |
title |
Freeze tolerance in an arctic Alaska stonefly |
title_short |
Freeze tolerance in an arctic Alaska stonefly |
title_full |
Freeze tolerance in an arctic Alaska stonefly |
title_fullStr |
Freeze tolerance in an arctic Alaska stonefly |
title_full_unstemmed |
Freeze tolerance in an arctic Alaska stonefly |
title_sort |
freeze tolerance in an arctic alaska stonefly |
publisher |
Company of Biologists |
publishDate |
2009 |
url |
http://jeb.biologists.org/cgi/content/short/212/2/305 https://doi.org/10.1242/jeb.020701 |
long_lat |
ENVELOPE(139.931,139.931,-66.690,-66.690) |
geographic |
Arctic Midwinter |
geographic_facet |
Arctic Midwinter |
genre |
Arctic Subarctic Alaska |
genre_facet |
Arctic Subarctic Alaska |
op_relation |
http://jeb.biologists.org/cgi/content/short/212/2/305 http://dx.doi.org/10.1242/jeb.020701 |
op_rights |
Copyright (C) 2009, Company of Biologists |
op_doi |
https://doi.org/10.1242/jeb.020701 |
container_title |
Journal of Experimental Biology |
container_volume |
212 |
container_issue |
2 |
container_start_page |
305 |
op_container_end_page |
312 |
_version_ |
1766332010871128064 |