10.5061/DRYAD.8SD03
Woods, H. Arthur
University of Montana
Data from: Ontogenetic changes in the body temperature of an insect herbivore
Dryad
dataset
2013
caterpillar
boundary layer
Manduca sexta
infrared
heat budget
2013-06-26T17:25:21Z
2013-06-26T17:25:21Z
en
https://doi.org/10.1111/1365-2435.12124
13871 bytes
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CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
1. Over ontogeny, many insect larvae grow substantially, through at least
several orders of magnitude in body size. Increasing size can profoundly
change how individuals interact with their environments, by altering the
opportunities for, and constraints on, feeding, changing the relative risk
and sources of predation, and shifting the relative importance of physical
factors in the environment. 2. Here I use eggs and larvae of Manduca
sexta, which are herbivores on solanaceous plants in the southwestern US,
to examine how body size affects body temperature. Larvae grow in excess
of 10,000-fold by mass in a few weeks, from 0.001-g hatchlings to 12 –
15-g 5th-instar larvae. 3. Using infrared thermography, I show that
increasing body size leads to large changes in body temperature: over
ontogeny, average larval temperature increased by 3 – 7°C. The
temperatures of eggs, hatchlings, and early larval instars were coupled to
leaf temperatures (Datura wrightii), which were much cooler than ambient
air temperatures. The temperatures of larger larvae, by contrast, were
similar to air temperatures, or somewhat higher. 4. Changing body
temperatures reflect that small and large larvae were immersed
differentially in leaf boundary layers, received different amounts of
incoming solar radiation, and used thermal heterogeneity on leaf surfaces
in different ways. 5. I develop a simple species distribution model that
links maximum observed air temperatures in the southwestern US with known
thermal tolerances of eggs and larvae. This model predicts that eggs of M.
sexta can occupy significantly larger fractions of the landscape than can
large larvae. 6. Large differences among stage-specific microclimates,
such as those observed for M. sexta, are likely to be general features for
insects and other organisms whose body sizes span large ranges, and
stage-specific microclimates pose general and largely unrecognized
problems for species distribution models.
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readme.txt for details.Woods_Figure_5_dataFile created in Microsoft Excel.
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Chihuahuan Desert
Arizona