TY - JOUR
T1 - Oxygen supply limits the chronic heat tolerance of locusts during the first instar only
AU - Youngblood, Jacob P.
AU - VandenBrooks, John M.
AU - Babarinde, Oluwatosin
AU - Donnay, Megan E.
AU - Elliott, Deanna B.
AU - Fredette-Roman, Jacob
AU - Angilletta, Michael J.
N1 - Funding Information:
This work was supported by Arizona State University's Graduate and Professional Student Association.
Funding Information:
This work was supported by Arizona State University’s Graduate and Professional Student Association .
Publisher Copyright:
© 2020 Elsevier Ltd
PY - 2020/11/1
Y1 - 2020/11/1
N2 - Although scientists know that overheating kills many organisms, they do not agree on the mechanism. According to one theory, referred to as oxygen- and capacity-limitation of thermal tolerance, overheating occurs when a warming organism's demand for oxygen exceeds its supply, reducing the organism's supply of ATP. This model predicts that an organism's heat tolerance should decrease under hypoxia, yet most terrestrial organisms tolerate the same amount of warming across a wide range of oxygen concentrations. This point is especially true for adult insects, who deliver oxygen through highly efficient respiratory systems. However, oxygen limitation at high temperatures may be more common during immature life stages, which have less developed respiratory systems. To test this hypothesis, we measured the effects of heat and hypoxia on the survival of South American locusts (Schistocerca cancellata) throughout development and during specific instars. We demonstrate that the heat tolerance of locusts depends on oxygen supply during the first instar but not during later instars. This finding provides further support for the idea that oxygen limitation of thermal tolerance depends on respiratory performance, especially during immature life stages.
AB - Although scientists know that overheating kills many organisms, they do not agree on the mechanism. According to one theory, referred to as oxygen- and capacity-limitation of thermal tolerance, overheating occurs when a warming organism's demand for oxygen exceeds its supply, reducing the organism's supply of ATP. This model predicts that an organism's heat tolerance should decrease under hypoxia, yet most terrestrial organisms tolerate the same amount of warming across a wide range of oxygen concentrations. This point is especially true for adult insects, who deliver oxygen through highly efficient respiratory systems. However, oxygen limitation at high temperatures may be more common during immature life stages, which have less developed respiratory systems. To test this hypothesis, we measured the effects of heat and hypoxia on the survival of South American locusts (Schistocerca cancellata) throughout development and during specific instars. We demonstrate that the heat tolerance of locusts depends on oxygen supply during the first instar but not during later instars. This finding provides further support for the idea that oxygen limitation of thermal tolerance depends on respiratory performance, especially during immature life stages.
KW - Heat tolerance
KW - Hypoxia
KW - OCLTT
KW - Ontogeny
KW - Survival
KW - Temperature
UR - http://www.scopus.com/inward/record.url?scp=85094813596&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85094813596&partnerID=8YFLogxK
U2 - 10.1016/j.jinsphys.2020.104157
DO - 10.1016/j.jinsphys.2020.104157
M3 - Article
C2 - 33098860
AN - SCOPUS:85094813596
SN - 0022-1910
VL - 127
JO - Journal of insect physiology
JF - Journal of insect physiology
M1 - 104157
ER -