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Reproductive Role of Infrared Radiation Sensors of Melanophila acuminata (Coleoptera: Buprestidae) at Forest Fires

DOI:10.1603/AN10076
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W. G. Evans
W. G. Evans
W. G. Evans
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Abstract

Based on the original experimental results from stimulating the infrared radiation sensors of Melanophila acuminata (DeGeer) (Coleoptera: Buprestidae), it has been concluded that the sensors function at forest fires by protecting beetles from hazardous conditions associated with a flaming environment while swarming, mating, and ovipositing on heated, exposed tree roots. The beetles are renowned for their rapid flight and for their exceptional dispersal capacity resulting in such a wide distribution that they come upon fires randomly. Thus, a case is made here that the infrared radiation sensors of M. acuminata and, presumably, other species in the genus, evolved not for distance perception of fires but for enhanced reproductive activities at them. An examination of the literature has revealed a long-standing interest in distances of perception of forest fires by the sensors, during which time increasingly longer distances have been claimed in various publications. These distances, however, cannot be accepted because there are no calculations supporting them, but just as important is that all of them, ranging up to 100 km in length, far exceed distances obtained by application of the inverse square law of physics where the intensity of radiation of a fire is inversely proportional to distance.
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FORUM
Reproductive Role of Infrared Radiation Sensors of Melanophila
acuminata (Coleoptera: Buprestidae) at Forest Fires
W. G. EVANS
1
Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E1
Ann. Entomol. Soc. Am. 103(6): 823Ð826 (2010); DOI: 10.1603/AN10076
ABSTRACT Based on the original experimental results from stimulating the infrared radiation
sensors of Melanophila acuminata (DeGeer) (Coleoptera: Buprestidae), it has been concluded that
the sensors function at forest Þres by protecting beetles from hazardous conditions associated with
a ßaming environment while swarming, mating, and ovipositing on heated, exposed tree roots. The
beetles are renowned for their rapid ßight and for their exceptional dispersal capacity resulting in such
a wide distribution that they come upon Þres randomly. Thus, a case is made here that the infrared
radiation sensors of M. acuminata and, presumably, other species in the genus, evolved not for distance
perception of Þres but for enhanced reproductive activities at them. An examination of the literature
has revealed a long-standing interest in distances of perception of forest Þres by the sensors, during
which time increasingly longer distances have been claimed in various publications. These distances,
however, cannot be accepted because there are no calculations supporting them, but just as important
is that all of them, ranging up to 100 km in length, far exceed distances obtained by application of the
inverse square law of physics where the intensity of radiation of a Þre is inversely proportional to
distance.
KEY WORDS Melanophila acuminata, infrared radiation sensors, forest Þres, reproduction
Adults of Melanophila acuminata (DeGeer) (Co-
leoptera: Buprestidae) are renowned for their disper-
sive powers (Wikars 1997) and their ubiquity at forest
Þres (Evans 1971). They are possibly better known,
however, for their infrared radiation (IR) sensors lo-
cated in an elliptical sensory pit adjacent to each
mesocoxa. These beetles are widely distributed over
the Northern Hemisphere wherever forest Þres occur,
even as far north as Fort Fitzgerald, AB, Canada, at
almost 60⬚ N (Specimens in the Entomology Collec-
tion, University of Alberta, Edmonton, AB, Canada).
Yet, their preferred surface temperatures are high,
ranging from 33.5 to 49.5⬚C, with a mean of 40.5⬚C
(Evans 1971), which is comparable with the mean
preferred surface temperature of ⬇40⬚C for second-
stage larvae of the desert locust Schistocerca gregaria
(Forskal) (Chapman 1998) at ⬇23⬚ N in the Sahara
desert.
My objectives here are to discuss the published
distances of perception of forest Þres by the IR sensors
and to propose a reproductive role for the sensors at
forest Þres.
Published Distances
The ability of M. acuminata to detect IR from forest
Þres has attracted much attention, both in the scien-
tiÞc literature and the popular media. Unfortunately,
there has been a trend over the years for increasing,
but unsubstantiated, reported distances of IR detec-
tion by the beetles. Some examples of published dis-
tances of IR perception (not accompanied by scien-
tiÞc calculations or experimental evidence) are given
below:
50 km. Gronenberg and Schmitz (1999), Ackerman
(2000), Anonymous (2003), Stone et al. (2004),
Brott (2006).
80 km. Biever (2004), Grimm (2004), Reese (2004),
Lee and Szema (2005), Mueller (2008).
100Ð150 km. Ishay et al. (2004).
50Ð100 miles. McConney (2009).
60Ð100 miles. Campbell et al. (2002).
These references represent sources citing, if at all,
other sources that include biological, engineering,
nanotech, neuroscience, military, and air force jour-
nals; a thesis; a popular magazine; and a nonpeer-
reviewed biological journal. At Þrst glance, they sug-
gest a widespread and ingrained acceptance of an
interesting aspect of insect behavior. Thus, the notion
that M. acuminata can detect IR from Þres consider-
able distances away is widely accepted in the literature
at this time. However, the lack of substantiation for
these distances represents a deplorable scientiÞc pre-
dicament that needs to be acknowledged. It seems that
1
Corresponding author, e-mail: wevans@ualberta.ca.
0013-8746/10/0823Ð0826$04.00/0 䉷 2010 Entomological Society of America
the only published distances over which IR might be
perceived by the beetleÕs sensors that involved calcu-
lations were 12 km (Schmitz and Bleckmann 1998)
and 1 km Hammer et al. (2001). The former distance
cannot accepted because of important assumptions in
calculations that were omitted (Hammer et al. 2001),
and the latter distance is unacceptable because in their
study the whole spherical chitinous structure of a sensor
was intentionally heated to induce a response when
stimulated by laser produced IR, in contrast to suggested
phasic responses produced by IR heating of the small
volume of air inside the sensor (Evans 2005). Thus, with
no acceptable published distances of perception of IR by
the sensors, calculations are now proposed to determine
IR intensities at distances from a Þre.
Radiation emitted by a Þre ⫽ Exitance (M), is cal-
culated from the following equation (Vincent 1990,
Wolfe 1998):
M ⫽␧⫻
␴
⫻ Þre area (W/m
2
),
where ␧ is the emissivity factor of a Þre of ⬇0.95 and
␴
is the StefanÐBoltzmann constant of 5.67 ⫻ 10
⫺8
W/m
2
⫻ K
4
, where K is temperature of a Þre in Kelvin.
Although peak temperatures of forest Þres are usually
provided in the literature, it is the average tempera-
ture of transient radiant ßux in time and place that is
pertinent here, such as the 1,000 K recorded at an
experimental Þre by Packham and Pompe (1971) or
the average of 900 K in a study of bushÞre radiant
ßuxes and temperatures, even though peak tempera-
tures of 1,200 K were encountered (Debnam 2005).
These average temperatures are close to the 926 K that
correspond to the peak wavelength of IR spectral
sensitivity of 3.13
␮
m (WienÕs displacement law) of
the beetleÕs sensors (Evans 1966).
Therefore, M in W/m
2
of a 400 m
2
area Þre is
5.67
⫺8
⫻ 926
4
⫻ 0.95 by 400 m
2
⫽ 199.5 W/m
2
.
The intensity of IR at a distance is inversely pro-
portional to the square of the distance (inverse square
law). Thus, dividing 199.5 W/m
2
by the square of a
distance from a Þre gives the IR intensity at that
distance. For example, at 1,000 m from a Þre, 199.5
W/m
2
/1,000 m
2
⫽ 0.0002 W/m
2
. This is an intensity
that is certainly not detectable by the IR sensors that
respond to 0.6 W/m
2
(see below); similarly, for 50 m,
where the intensity is 0.08 W/m
2
. But at that distance,
other stimuli such as visual, olfactory (Schutz et al.
1999), and thermal (Evans 1971), probably invoke
responses that guide the beetles to a Þre. Thus, these
results support a conclusion that no published dis-
tances of IR perception by the sensors are valid and
that the IR sensors of M. acuminata and other species
of Melanophila that have the sensors, function at or
near Þres.
Proposed Role of the Sensors in Reproduction
Sensor sensitivity of IR perception by M. acuminata
beetles was originally determined by stimulating the
sensors of one of the mesothoracic sensory pits, with
an IR source of 0.6 W/m
2
from ⬇2 cm away (Evans
1966). The response was a distinct twitching of the
antenna on the same side of the insect as the sensory
pit being stimulated. Such a short distance for a pos-
itive response suggests that the beetles were respond-
ing as though at a Þre emitting this radiation, and there
are several reasons that support this view. Orienting to
a point source, such as a distant Þre, is not a role for
paired lateral groups of sensors with Þelds of view that
do not overlap anteriorly (Evans and Kuster 1980).
Instead, they would be much more practical for per-
ceiving IR from a wall of ßames as the beetles ßy
parallel to them. In addition, perception of a distant
point source of radiation would not be enhanced by
the beetleÕs phasic IR sensors (Evans 2005) that are
capable of detecting ⬇8-ms changes in motions of
ßames during ßight. Finally, as calculated above, dis-
tance perception of IR from Þres is restricted to ⬍50
m, suggesting that the IR sensors function at or very
close to Þres, agreeing with the suggestion that repro-
duction takes place there (Linsley 1943, Bily´ 1982).
A major characteristic of the beetles is their swarm-
ing behavior toward a Þre at meter heights above the
ground, as noted by Linsley (1933), ÞreÞghters (Eaton
and Kaufman 2007), or, for Melanophila consputa
(Lec), other individuals (Van Dyke 1926). Beetles
also were observed at ground level at a smelter plant
(Linsley 1943), at an oil sludge Þre (Evans 1971), and
a small scrub Þre in Alberta, Canada (unpublished
data). This behavior indicates a predilection for ßying
close to the ground, where mating and oviposition take
place, thus avoiding burning branches higher up.
Swarming has been previously linked to reproduction
along with the suggestion that swarming, mating, and
oviposition are elicited by Þres (Bily´ 1982, cited in
Wikars [1997)]).
If distance perception of Þres is not an IR sensor
option, then the beetles reach Þres by other means.
Insects dependent on ephemeral habitats, such as for-
est Þres, must have a large dispersal and reproductive
capacity (Southwood 1977). Wikars (1997) enlarged
on this theme by stating that M. acuminata beetles
have an exceptional dispersal capacity as exempliÞed
by their appearance on sea shores very far from forest
Þres. It is very likely that the beetles reach Þres by
chance through these highly dispersive activities. This
behavior also results in beetles reaching campÞres,
and trees freshly killed by wind storms or by logging
(Burke 1919; Evans 1962, 1971). Within short dis-
tances of Þres, dispersing beetles may reach them by
detecting smoke with their antennal olfactory sensors
(Schutz et al. 1999), or temperature sensors (Evans
1971), or perhaps visually as well, resulting eventually
in swarms of beetles ßying close to a Þre where heat
and smoke stimulate ßight, mating, and oviposition.
Reproduction at Þres is greatly increased, because
there are no predators or competitive species of wood-
boring insects, and development is rapid as reduced
length of development ensues when eggs are depos-
ited in bark heated by IR. Palm (1949) recorded a case
where, at the time of a Þre, development of the bee-
tles, which normally takes a year, took 2 mo from
oviposition to pupation. Assuming more or less con-
stant arrivals at a Þre (Van Dyke 1926), beetles at the
824 A
NNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA Vol. 103, no. 6
downwind moving Þre front are continually being
replaced by fresh beetles, resulting in increased re-
production, a speciÞc requirement for insects of
ephemeral habitats (Southwood 1977).
The function of the IR sensors is very evident at a
forest Þre where conditions are unpredictable be-
cause many complex factors are involved, such as
rapid changes in wind speed or direction, topography,
kinds of fuels, atmospheric moisture content, and
weather. Flame ßare-ups can be common, as can
pieces of burning material (Þrebrands) that are car-
ried into the air, to land wherever. It is very likely that
ßying beetles avoid these hazards by detecting sudden
changes in radiant ßux. Thus, it can be concluded that
the sensors evolved to enhance reproductive success
directly at Þres.
Acknowledgments
I extend my most sincere thanks to George E. Ball (De-
partment of Biological Sciences, University of Alberta) for
critical review of the biological aspects of the manuscript.
And I am most grateful to E. O. Wilson (Department of
Organismic and Evolutionary Biology, Harvard University,
Boston, MA) and to Peter Lawrence (Department of Zool-
ogy, University of Cambridge, Cambridge, United Kingdom)
for advice on dealing with the difÞcult problem of the many
unconÞrmed claims of distance perception of Þres by M.
acuminata. I also thank Chris Evans (Royal Alexandra Hos-
pital, Edmonton, AB, Canada) and Claire Jones (Ichor Med-
ical Systems, San Diego, CA) for critically reviewing the
manuscript. Finally, thanks to Frank Weichman (Depart-
ment of Physics, University of Alberta) for ongoing interest
in the research. The support and encouragement of the
Department of Biological Sciences (University of Alberta) is
gratefully acknowledged.
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826 ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA Vol. 103, no. 6
... Western fence lizards (Sceloporus occidentalis) ( Figure IA) in southern California perch on blackened stalks of burned shrubs (that closely match the color of their scales) for several years postfire, but avoid perching on white stalks [96], an adaptive behavior reinforcing dark morphology in lizards in fire-prone shrublands. Melanophila acuminata beetles ( Figure IB) have evolved infrared sensory pits on the underside of their midsection (thorax) that allow them to sense forest fires and help protect individuals engaging in reproductive behaviors while fires are still burning [70]. California spotted owls (Strix occidentalis occidentalis) ( Figure IC) preferentially hunt in small (e.g., <1-10 hectare) patches of forests that have recently burned at high severity, where they find high densities of their small mammal prey [97]. ...
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... Western fence lizards (Sceloporus occidentalis) ( Figure IA) in southern California perch on blackened stalks of burned shrubs (that closely match the color of their scales) for several years postfire, but avoid perching on white stalks [96], an adaptive behavior reinforcing dark morphology in lizards in fire-prone shrublands. Melanophila acuminata beetles ( Figure IB) have evolved infrared sensory pits on the underside of their midsection (thorax) that allow them to sense forest fires and help protect individuals engaging in reproductive behaviors while fires are still burning [70]. California spotted owls (Strix occidentalis occidentalis) ( Figure IC) preferentially hunt in small (e.g., <1-10 hectare) patches of forests that have recently burned at high severity, where they find high densities of their small mammal prey [97]. ...
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... For example, cultural fire use could increase the genetic connectivity of populations of Boisduval's blue butterfly (P. icarioides) in Yosemite National Park (CA, USA) [70], thereby altering the distribution of beneficial alleles among subpopulations and increasing species evolutionary resilience. ...
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Full-text available
  • Aug 2022
Many insects are drawn to the heat, ash, and smoke produced by forest fires and arrive in large numbers at recent burns, often while the fire is still active. Some of these insects are pyrophilic and reproduce exclusively in the immediate aftermath of fire but are rarely, if ever, collected from unburnt habitats. Numerous observations made at active fires note an apparent preference among some pyrophilic insects to oviposit exclusively in the burnt portions of trees, raising broader questions about the adaptive benefits of reproduction in the post‐burn environment. Here, we tested whether the reproductive output of pyrophilic ground beetles (i.e., Sericoda spp.) increased in heat‐sterilized soils. In the first experiment, the eggs of Sericoda quadripunctata were reared in three types of soil collected from burnt forests: recently burnt soil (collected 1–2 weeks after the fire), soil collected 1 year after burn, and soil from an unburnt patch of forest adjacent to the fire. Daily monitoring through a dissecting microscope documented extensive predation of eggs by soil microarthropods (mites, springtails, and nematodes), especially in 1‐year‐old and unburnt soil treatments. This led to a second experiment that included the same three treatments and an additional fourth soil treatment: recently, burnt soil reheated to 100°C for 2 h (i.e., reheated soil). In this experiment, male and female pairs (n = 100) of Sericoda obsoleta were reared for 14 days in jars containing 90 g of soil corresponding to each of the four soil treatments. Reproductive output, measured as the number of larvae produced by each breeding pair, was significantly higher in the reheated soil, suggesting that heat sterilization and removal of soil‐dwelling predators improved egg survival. Our findings suggest that pyrophily in insects may have evolved as a means of increasing reproductive output in the post‐burn environment through access to heat‐sterilized ovipositing substrates. Furthermore, the abrupt disappearance of Sericoda and other pyrophilic insects following fire may be explained by suboptimal reproductive conditions as the burn is colonized by other organisms and by local emigration in favor of other recent burns on the landscape.
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... However, the contribution of this food source to their diet and survival during the dry season remains to be quantified ( Table 1). Insects that have fire detectors and are attracted to the flames also benefit directly from fire (Schutz et al. 1999;Evans 2010;see below). ...
... There are some cases in which we find evidence of specific adaptations to survive the new environment or to exploit the newly available resources, and in this includes some morphological adaptations (Table 3). Perhaps the best-documented adaptation to fire in the animal kingdom is the presence of fire detectors in a number of insect species (Schutz et al. 1999;Evans 1966Evans , 2010. This is not an adaptation to avoid fires but rather enables them to locate them and make use of new resources in the postfire environment. ...
Towards an understanding of the evolutionary role of fire in animals
Article
Full-text available
Wildfires underpin the dynamics and diversity of many ecosystems worldwide, and plants show a plethora of adaptive traits for persisting recurrent fires. Many fire-prone ecosystems also harbor a rich fauna; however, knowledge about adaptive traits to fire in animals remains poorly explored. We review existing literature and suggest that fire is an important evolutionary driver for animal diversity because (1) many animals are present in fire-prone landscapes and may have structural and phenotypic characters that contribute to adaptation to these open landscapes; and (2) in some cases, animals from fire-prone ecosystems may show specific fire adaptations. While there is limited evidence on morphological fire adaptations in animals, there is evidence suggesting that different behaviors might provide a rich source of putative fire adaptations; this is because, in contrast to plants, most animals are mobile, unitary organisms, have reduced survival when directly burnt by fire and can move away from the fire. We call for research on fire adaptations (morphological, behavioral, and physiological) in animals, and emphasize that in the animal kingdom many fire adaptations are likely to be behavioral. While it may be difficult to discern these adaptations from other animal behaviors, making this distinction is fundamental if we want to understand the role of fire in shaping biodiversity. Developing this understanding is critical to how we view and manage our ecosystems in the face of current global and fire regime changes.
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... Other species survive by burrowing into the soil (Thom et al., 2015), and fire can even be a cue for emergence (Jacobs et al., 2011), as it is for the germination of some plants (Keeley et al., 2012). Finally, exogenous recolonisation, a case in which individuals from unaffected areas relocate in the burnt zone after the fire, is well described, particularly in saproxylic insects (Evans, 2010). ...
Comparative assessment of heat tolerance in weevils associated with a fire-prone ecosystem
Article
Full-text available
1. Fire is an important cause of disturbance which directly shapes many ecosystems worldwide. While the effect of fire on the distribution and regeneration of plant species has been widely documented, little is known on how phytophagous insects are reacting to these disturbances. 2. This study explores the survival strategies of various weevil species, a highly diverse phytophagous beetle group in fire-prone ecosystems of the biodiversity hotspot of the Cape Floristic Region in South Africa. More specifically, we investigated how the lifestyle of species (location of larval development, phenology of adults, and flight ability) correlates with heat tolerance. We hypothesized that wingless species in particular will show better tolerance to heat as they have a limited ability to escape fire rapidly and usually remain hidden in the soil. 3. The thermal tolerance of a set of sixteen species with divergent lifestyles and geographic distribution was measured using a standard heat knockdown protocol at 48°C. Respirometry was then performed on the most resistant species using a ramping protocol in order to determine CTmax. 4. Our results show that the species tested exhibit high variation in thermal tolerance across taxonomic groups, clustering into three modalities: weak, intermediate, and high tolerance to heat stress. In addition, life history traits (diurnal vs. nocturnal adult activity and location of juvenile stages in plant tissues) likely better explain thermal tolerance at the species level than flight ability or the fire-proneness of ecosystems. Finally, results revealed that some non-flying weevil species are highly heat tolerant with CTmax values reaching up to 50.2 and 51.9°C in species among the Ocladiinae and Brachycerinae subfamilies, respectively. 5. Climate change is leading to an increase in the impact and frequency of fires. In this context, this study highlights the diversity of strategies developed by arthropods to escape extreme heat in fire prone ecosystems. Further work is necessary to examine the generality of these patterns across other fire prone ecosystems to better understand behavioural compensation and evolutionary responses, especially given the forecast increases in fire driven by drying and warming associated with climate change.
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... These beetles mainly live and grow on burnt trees or wood, therefore ensuring proximity to a set of potentially ignitable patch of forests. See [3]. These patches of burnt trees and wood help them reproduce, from which the entire process of fire-detection has emerged. ...
Bio-Inspirations - Melanophila Acuminata can Sense and Detect Forest Fires
Article
  • Aug 2022
Forest-fires are caused due to various factors including natural ones, such as hot lightning striking the ignitable trees, and human ones such as negligent use of fire or fire-causing products like cigarettes and explosives, disruptive machinery deployed within the forest, etc. The spread of these fires, however, is largely determined by parameters such as temperature, wind, relative humidity, and rain; unsurprisingly, the most prominent of these factors is the temperature. Detection of anomalies in the temperature can be a crucial indication towards the possibility of a fire, therefore enabling a potentially quicker response and minimising the loss of land and other resources, besides human life. A specific beetle called the Fire Beetle, or the melanophila acuminata, is known to have evolved with a collection of sensors which can detect IR radiation with remarkable sensitivity, even from long distances. These beetles can potentially sense the emergence of a fire from as long as a few miles away. Since early detection of forest-fires is a decisive step towards dealing with it, taking inspiration from melanophila acuminata can be a way of doing so.
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A wake-up call for sleepy lizards: the olfactory-driven response of Tiliqua rugosa (Reptilia: Squamata: Sauria) to smoke and its implications for fire avoidance behavior
Article
  • Dec 2019
Many reptiles occur in landscapes that are prone to fire, yet limited information is available on the cues these species use to detect approaching fires or their immediate and preemptive behavioral responses to fire stimuli. Here, we describe the behavioral response of ten captive sleepy lizards (Tiliqua rugosa) that were inadvertently exposed to light smoke. Proportionately, significantly more individuals that were exposed to smoke exhibited increased activity, including swift pacing, repeated escape behaviors, and rapid olfactory-related tongue-flicking than those that were not exposed, which did not exhibit any such changes in activity or behaviors. Additionally, of 14 reptile species housed in the smoke-affected area, T. rugosa was the only species to exhibit a noticeable behavioral response. Since there were no visible flames, sounds of fire, reductions in light levels or visibility, or increases in temperature, these observations suggest that T. rugosa detects smoke through olfaction. Moreover, because most individuals were captive-born and, therefore, naïve to smoke or fire, this response likely represents an adaptive innate behavioral response of the species. We discuss these findings in the light of fire avoidance behavior in Tiliqua and reptiles in general.
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Generalized fire response strategies in plants and animals
Article
  • Sep 2018
Despite the existing large body of research on plant‐animal interactions, plant research and animal research are still relatively independent and asymmetrical in relation to disturbance. Animals and plants are likely to have different fire responses, yet biodiversity studies in relation to disturbance may benefit from a more integrated functional approach across kingdoms. This would also force us to go deeper into the biological mechanisms and scales for persistence than a taxonomic‐based classification. An integrated view of plant and animal responses would enable us to learn from a great variety of life forms and benefit from expertise in complementary disciplines. To achieve this integrated view, I propose a functional classification for both plants and animals in relation to their fire response strategy. This classification includes the following strategies: resistance, refugia, avoidance, dormancy, recolonization, crypsis and intolerance. Given the limited knowledge of fire responses for many organisms, and especially for many animals, this classification may require further development. However, it provides a framework that facilitates finding knowledge gaps and directing future research for gaining a better understanding of the role of fire on biodiversity. This article is protected by copyright. All rights reserved.
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Chaparral and Pinyon‐Juniper Woodlands
Chapter
  • Jul 2015
Chaparral is a name popularly applied to various shrub communities in western North America. A second and separate region of chaparral occurs in parts of Arizona and Mexico. Chaparral communities extend from sea level to 2000 m (6562 feet) and, within this range, generally favor steep slopes with nutrient-deficient and poorly developed soils. Sclerophytic leaves are the key feature of chaparral vegetation. As well as coping with drought, chaparral communities also deal in various ways with fire. Chaparral, like the term forest or mangrove, is a type of vegetation represented by several taxa and communities, of which three associations in California are paramount. Interior chaparral develops in a climatic regime unlike the Mediterranean pattern that favors coastal chaparral. Allelopathy is better illustrated in chaparral, where it represents another dimension of physiological ecology. In ironic consequence, sizeable areas of Pinyon-Juniper woodlands have been completely cleared and seeded with grasses to restore grazing.
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Fundamentals of infrared and visible detector operation and testing: Second edition
Book
  • Oct 2015
Presents a comprehensive introduction to the selection, operation, and testing of infrared devices, including a description of modern detector assemblies and their operation This book discusses how to use and test infrared and visible detectors. The book provides a convenient reference for those entering the field of IR detector design, test or use, those who work in the peripheral areas, and those who teach and train others in the field. Chapter 1 contains introductory material. Radiometry is covered in Chapter 2. The author examines Thermal detectors in Chapter 3; the "Classical" photon detectors - simple photoconductors and photovoltaics in Chapter 4; and "Modern Photon Detectors" in Chapter 5. Chapters 6 through 8 consider respectively individual elements and small arrays of elements the "readouts" (ROICs) used with large imaging arrays; and Electronics for FPA Operation and Testing. The Test Set and The Testing Process are analyzed in Chapters 9 and 10, with emphasis on uncertainty and trouble shooting. Chapters 11 through 15 discuss related skills, such as Uncertainty, Cryogenics, Vacuum, Optics, and the use of Fourier Transforms in the detector business. Some highlights of this new edition are that it Discusses radiometric nomenclature and calculations, detector mechanisms, the associated electronics, how these devices are tested, and real-life effects and problems Examines new tools in Infrared detector operations, specifically: selection and use of ROICs, electronics for FPA operation, operation of single element and very small FPAs, microbolometers, and multi-color FPAs Contains five chapters with frequently sought-after information on related subjects, such as uncertainty, optics, cryogenics, vacuum, and the use of Fourier mathematics for detector analyses Fundamentals of Infrared and Visible Detector Operation and Testing, Second Edition, provides the background and vocabulary necessary to help readers understand the selection, operation, and testing of modern infrared devices.
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The Insects: Structure and Function
Article
  • Nov 1998
Preface Part A. The Head, Ingestion, Utilization and Distribuiton of Food: 1. Head 2. Mouthparts and feeding 3. Alimentary canal, digestion and absorption 4. Nutrition 5. Circulatory system, blood and immune system 6. Fat body Part B. The Thorax, Muscles and Locomotion: 7. Thorax 8. Legs and locomotion 9. Wings and flight 10. Muscles Part C. The Abdomen, Reproductive System and Development: 11. Abdomen 12. Reproductive system: male 13. Reproductive system: female 14. The egg and embryology 15. Postembryonic development Part D. The Integument, Gas Exchange and Homeostasis: 16. Integument 17. Gaseous exchange 18. Excretion and salt and water regulation 19. Thermal relations Part E. Communication: I. Physiological Co-ordination within the Insects: 20. Nervous system 21. Endocrine System II. Perception of the Environment: 22. Visual system 23. Mechanoreception 24. Chemoreception III. Communication with other Organisms: 25. Color and light production 26. Mechanical communication: sound production 27. Chemical communication: pheromones and chemicals with interspecific significance Species index Subject index.
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Perception of Infrared Radiation from Forest Fires by Melanophila Acuminata De Geer (Buprestidae, Coleoptera)
Article
  • Nov 1966
When Melanophila acuminata De Geer was stimulated with infrared radiation, responses were obtained in the range of from 2.0 to 6.0@m. The highest sensitivity was found to be, however, in the 2.5 to 4.0@m range at an energy level of 6.0 x 10^@o^5 watts per cm^2. The organs which detect infrared radiation are found on the mesothorax adjacent to the coxal cavities. Through consideration of the physical characteristics of infrared radiation it has been possible to estimate the distances from which forest fires of various sizes could be detected by M. acuminata. For instance, the radiation from a 50 acre fire in mountainous terrain could be detected by this insect from 5 km away but the same size fire on flat land could only be detected from 1 km. The ecological implications of the habits of this insect are also discussed.
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