Morpho Peleides Research Articles

Microstructures of responsive photonic crystals on the stimuli-responsive performance: Effects and simulation

Nature provides abundant photonic structures which give a great inspiration on the synthesis of stimuli-responsive photonic crystals (PCs) with unique structures. However, the intrinsic effects of microstructures on the responsive properties of the hierarchical PCs are still not clear. Herein, the relationship between the photonic structures and the responsive properties is investigated by choosing three natural photonic structures replicated from templates, Morpho Menelaus and Morpho peleides both with a 1D tree-like hierarchical structure while having eight and four layers, respectively and Papilio paris, with an eight layered 1D concave structure. Humidity responsive PCs were prepared by in-situ polymerizing polyacrylamide (PAAm) onto the surface of the butterfly wing scales. The 1D concave (Papilio paris) structured PCs exhibited a higher humidity sensitivity: a wavelength redshift of 92 nm when the relative humidity rose from 11 to 97 %, as compared with the Morpho menelaus PCs, which have about 70 nm redshift for the same rise of the relative humidity. The eight layer 1D tree-like structured Morpho menelaus PCs had a higher reflectance intensity. The results were also supported by a finite-difference time-domain (FDTD) simulation. This work paves a new avenue to design responsive PCs with a diversity of structures from nature and controllable responsive properties.

What does a butterfly hear? Physiological characterization of auditory afferents in Morpho peleides (Nymphalidae).

Many Nymphalidae butterflies possess ears, but little is known about their hearing. The tympanal membrane of butterflies typically comprises distinct inner and outer regions innervated by auditory nerve branches NII and NIII and their respective sensory organs. Using the Blue Morpho butterfly (Morpho peleides) as a model, we characterized threshold and suprathreshold responses of NII and NIII. Both are broadly tuned to 1-20kHz with best frequencies at 1-3kHz, but NIII is significantly more sensitive than NII. The compound action potentials (CAPs) of both branches increase their first peak amplitudes and areas in response to higher sound levels. NII and NIII differed in their suprathreshold CAP responses to sound frequencies, with stronger responses to 1-3 and 4-6kHz, for NIII and NII respectively; results that are consistent with tympanal membrane mechanics. These results indicate that butterflies are capable of amplitude and frequency discrimination. Both auditory branches responded to playbacks of the flight and calls of predatory birds. We propose that the ears of butterflies, like those of many vertebrate prey such as some rabbits and lizards, function primarily in predator risk assessment.

Los agroecosistemas cafetaleros modernos y su relación con la conservación de mariposas en paisajes fragmentados

Land use change by the intensification of agriculture contributes to tropical forest fragmentation and biodiversity loss. In this sense, in comparison with traditional agroforestry systems (AFS), modern AFS are considered irrelevant for the conservation of biodiversity of tropical forest fragments. However, there is an increasing trend toward the establishment of different types of modern AFS. Owing to the sensitivity to environmental changes, we evaluated the biodiversity of butterflies in AFS with Coffea arabica and Erythrina poeppigiana (CP), and intermixed with Musa spp. (CPM) or Cordia alliodora (the only native species of AFS) (CPL), as well as premontane very humid forest fragments in the Volcánica Central-Talamanca Biological Corridor, Costa Rica. In six representative sites of each system we set up three parallel 80 m line-transects, separated by a distance of 25 m. Each coffee farm and forest fragment (FR) was surveyed during 1.5 hours to record butterflies. All sites were sampled once a month from May to July 2007. We obtained 4.5 hours of sampling/site, and 27 hours of sampling/habitat. Both CP and CPM together had a butterflies’ species composition which differed from CPL and FR. The indicator species of both CP and CPM together were Hermeuptychia hermes and Anartia jatrophae which are typical of open areas. CPL resulted with the species of secondary forests Heliconius erato petiverana and Pareuptychia ocirrhoe as indicators. In contrast, FR resulted with several indicator species typical of closed canopy forests such as Pierella helvina incanescens, Caligo eurilochus, and Morpho peleides limpida. Moreover, the richness of species was similar among coffee AFS. Furthermore, the richness of species of each coffee AFS was lower in comparison with FR. However, among coffee AFS, CPL harbored higher diversity (Exp(H’)) of forest butterflies than CP. Also, CPM was higher in abundance of frugivorous butterflies in relation with CP and CPL. In fragmented forests, coffee farms with exotic shade species combined at least with a native tree or fruit species, can be a better habitat for forest butterflies than those dominated by an exotic monospecific shade.

Feeding behavior of Morpho butterflies (Lepidoptera: Nymphalidae: Morphinae) in a seasonal tropical environment

Observations in a semi-deciduous tropical wet forest in Guanacaste, Costa Rica, early in the dry season (December 1973 ) revealed that adults of the butterfly Morpho peleides (Lepidoptera: Nymphalidae: Morphinae) feed on tiny sap flows on exposed roots of the tree Samanea saman (Leguminoseae). These observations supplement earlier studies on the association of the butterflies with fallen, decaying fruits of the tree Guazuma ulmifolia (Sterculiaceae) in the same forest but during the previous dry season (January 1973). Morphoes collect in small groups of both sexes on the tree sap flows along with several species of ants. These feeding clubs, which are formed daily, usually in the afternoons, are tightly structured in that adults feed very closely together with no indications of agonistic behavior or courtship. When suddenly disturbed, the butterflies cease feeding and fly around the area before settling on nearby vegetation. The feeding behavior is different when morphoes feed on juices of Guazuma fruits: adults are widely dispersed and no feeding clubs are formed. Guazuma trees are more abundant in this forest and scattered over a larger area than the few Samanea trees. The association of Pierella luna; with the tree sap flows and the conspicuous lack of Caligo memmon, both abundant butterflies, is discussed from the standpoint of phylogenetic relationship between the Satyrinae and Morphinae. The implications of the changeover in feeding behavior of Morpho are discussed in terms of seasonality and destruction of forests by agricultural practices. Experiments employing baits predict changes in the dispersion of the adult population at different times during the dry season.

Morpho peleides butterfly wing imprints as structural colour stamp

This study presents the replication of a color-causing nanostructure based on the upper laminae of numerous cover scales of Morpho peleides butterfly wings and obtained solely by imprinting their upper-wing surfaces. Our results indicate that a simple casting technique using a novel integrated release agent can obtain a large positive replica using negative imprints via Polyvinylsiloxane. The developed method is low-tech and high-yield and is thus substantially easier and less expensive than previous methods. The microstructures were investigated with light microscopy, the nanostructures with both scanning and transmission electron microscopy, and the reflections with UV visible spectrometry. The influence of the release agent and the quality of the master stamp were determined by comparing measurements of the cover-scale sizes and their chromaticity values obtained by their images and with their positive imprints. The master stamp provided multiple positive replicas up to 3 cm2 in just 1 h with structural coloration effects visible to the naked eye. Thus, the developed method proves the accuracy of the replicated nanostructure and its potential industrial application as a color-producing nanostamp.

Blue Morpho Butterfly Morpho peleides Kollar (Lepidoptera: Nymphalidae)

The blue morpho butterfly, also known as the peleides blue morpho or common blue morpho, is a brightly colored butterfly abundant in tropical environments in Central and South America. It can be seen flying in open areas such as paths, trails, forest edges, and rivers. In the United States, it is often featured in museums and zoos that have butterfly houses or butterfly rainforests. This five-page fact sheet about the popular butterfly was written by Haleigh A. Ray and Jacqueline Y. Miller, and published by the UF Department of Entomology and Nematology, August 2015. (Photo credit: Andrei Sourakov, McGuire Center or Lepidoptera and Biodiversity, Florida Museum of Natural History, University of Florida)
 EENY631/IN1101: Blue Morpho Butterfly Morpho peleides Kollar (Lepidoptera: Nymphalidae) (ufl.edu)

Hearing in the crepuscular owl butterfly (Caligo eurilochus, Nymphalidae).

Tympanal organs are widespread in Nymphalidae butterflies, with a great deal of variability in the morphology of these ears. How this variation reflects differences in hearing physiology is not currently understood. This study provides the first examination of hearing organs in the crepuscular owl butterfly, Caligo eurilochus. We examined the tuning and sensitivity of the C. eurilochus hearing organ, called Vogel's organ, using laser Doppler vibrometry and extracellular neurophysiology. We show that the C. eurilochus ear responds to sound and is most sensitive to frequencies between 1 and 4 kHz, as confirmed by both the vibration of the tympanal membrane and the physiological response of the associated nerve branches. In comparison to the hearing of its diurnally active relative, Morpho peleides, C. eurilochus has a narrower frequency range with higher auditory thresholds. Hypotheses explaining the function of hearing in this crepuscular butterfly are discussed.

If a bird flies in the forest, does an insect hear it?

Birds are major predators of many eared insects including moths, butterflies, crickets and cicadas. We provide evidence supporting the hypothesis that insect ears can function as 'bird detectors'. First, we show that birds produce flight sounds while foraging. Eastern phoebes (Sayornis phoebe) and chickadees (Poecile atricapillus) generate broadband sounds composed of distinct repetitive elements (approx. 18 and 20 Hz, respectively) that correspond to cyclic wing beating. We estimate that insects can detect an approaching bird from distances of at least 2.5 m, based on insect hearing thresholds and sound level measurements of bird flight. Second, we show that insects with both high and low frequency hearing can hear bird flight sounds. Auditory nerve cells of noctuid moths (Trichoplusia ni) and nymphalid butterflies (Morpho peleides) responded in a bursting pattern to playbacks of an attacking bird. This is the first study to demonstrate that foraging birds generate flight sound cues that are detectable by eared insects. Whether insects exploit these sound cues, and alternatively, if birds have evolved sound-reducing foraging tactics to render them acoustically 'cryptic' to their prey, are tantalizing questions worthy of further investigation.

Replication of homologous optical and hydrophobic features by templating wings of butterflies Morpho menelaus

The revealed “Christmas-tree” nanostructures in the cover and ground scales of the butterfly Morpho menelaus are responsible for the observed iridescent blue color and the diffraction pattern of the wings. The aspect ratio of nanostructures in ground scales is more than 5 times higher than that of Morpho peleides cover scales. Inspired by the butterfly, artificial nanostructures are fabricated successfully by templating the scales imbricating in the wings with low-temperature atomic layer deposition (ALD) methods. Through structural characterizations and optical measurements, we reveal that the hybrid structures inherit not only the morphology of the scales with high fidelity but also the homologous optical features including iridescence and diffraction. Besides, water contact angle measurements on both uncoated and coated wings show hydrophobic results. The integration of bio-templates and ALD methods provide a potential route to fabricate the nanostructures with multi-functional features, which may be especially crucial in the applications of innovative functional optical devices.

Auditory mechanics and sensitivity in the tropical butterfly Morpho peleides (Papilionoidea, Nymphalidae)

The ears of insects exhibit a broad functional diversity with the ability to detect sounds across a wide range of frequencies and intensities. In tympanal ears, the membrane is a crucial step in the transduction of the acoustic stimulus into a neural signal. The tropical butterfly Morpho peleides has an oval-shaped membrane at the base of the forewing with an unusual dome in the middle of the structure. We are testing the hypothesis that this unconventional anatomical arrangement determines the mechanical tuning properties of this butterfly ear. Using microscanning laser Doppler vibrometry to measure the vibrational characteristics of this novel tympanum, the membrane was found to vibrate in two distinct modes, depending on the frequency range: at lower frequencies (1-5 kHz) the vibration was focused at the proximal half of the posterior side of the outer membrane, while at higher frequencies (5-20 kHz) the entire membrane contributed to the vibration. The maximum deflection points of the two vibrational modes correspond to the locations of the associated chordotonal organs, suggesting that M. peleides has the capacity for frequency partitioning because of the different vibrational properties of the two membrane components. Extracellular nerve recordings confirm that the innervating chordotonal organs respond to the same frequency range of 1-20 kHz, and are most sensitive between 2 and 4 kHz, although distinct frequency discrimination was not observed. We suggest that this remarkable variation in structure is associated with function that provides a selective advantage, particularly in predator detection.

Structural colors from Morpho peleides butterfly wing scales

A male Morpho peleides butterfly wing is decorated by two types of scales, cover and ground scales. We have studied the optical properties of each type of scales in conjunction with the structural information provided by cross-sectional transmission electron microscopy and computer simulation. The shining blue color is mainly from the Bragg reflection of the one-dimensional photonic structure, e.g., the shelf structure packed regularly in each ridges on cover scales. A thin-film-like interference effect from the base plate of the cover scale enhances such blue color and further gives extra reflection peaks in the infrared and ultraviolet regions. The analogy in the spectra acquired from the original wing and that from the cover scales suggests that the cover scales take a dominant role in its structural color. This study provides insight of using the biotemplates for fabricating smart photonic structures.

Hearing in a diurnal, mute butterfly,Morpho peleides(Papilionoidea, Nymphalidae)

Butterflies use visual and chemical cues when interacting with their environment, but the role of hearing is poorly understood in these insects. Nymphalidae (brush-footed) butterflies occur worldwide in almost all habitats and continents, and comprise more than 6,000 species. In many species a unique forewing structure--Vogel's organ--is thought to function as an ear. At present, however, there is little experimental evidence to support this hypothesis. We studied the functional organization of Vogel's organ in the common blue morpho butterfly, Morpho peleides, which represents the majority of Nymphalidae in that it is diurnal and does not produce sounds. Our results confirm that Vogel's organ possesses the morphological and physiological characteristics of a typical insect tympanal ear. The tympanum has an oval-shaped outer membrane and a convex inner membrane. Associated with the inner surface of the tympanum are three chordotonal organs, each containing 10-20 scolopidia. Extracellular recordings from the auditory nerve show that Vogel's organ is most sensitive to sounds between 2-4 kHz at median thresholds of 58 dB SPL. Most butterfly species that possess Vogel's organ are diurnal, and mute, so bat detection and conspecific communication can be ruled out as roles for hearing. We hypothesize that Vogel's organs in butterflies such as M. peleides have evolved to detect flight sounds of predatory birds. The evolution and taxonomic distribution of butterfly hearing organs are discussed.

Visual sensitivity in the crepuscular owl butterfly Caligo memnon and the diurnal blue morpho Morpho peleides: a clue to explain the evolution of nocturnal apposition eyes?

Insects active in dim light, such as moths and many beetles, normally have superposition compound eyes to increase photon capture. But there are nocturnal and crepuscular insects - such as some species of bees, wasps and butterflies - that have apposition compound eyes. These are likely to have adaptations - including large eye and facet size and coarsened spatial and temporal resolution - that improve their sensitivity and thus their visual reliability. Is this also true for crepuscular insects that are active at intermediate intensities? To test this hypothesis, the visual performance of two closely related butterflies, the diurnal blue morpho Morpho peleides and the crepuscular owl butterfly Caligo memnon, were compared. Compared to the diurnal M. peleides, the crepuscular C. memnon does not appear to be adapted to a nocturnal lifestyle in terms of spatial resolution: the interommatidial angle Delta is similar in both species, and acceptance angles, Deltarho, are only marginally larger in C. memnon. Moreover, temporal resolution is only a little coarser in C. memnon compared to M. peleides. Using a model for sensitivity, we found that the eyes of C. memnon are about four times as light-sensitive as those of M. peleides in the frontal visual field, much of this difference being due to the larger facet diameters found in C. memnon. In summary, greater visual sensitivity has evolved in C. memnon than in M. peleides, showing that adaptations that improve sensitivity can be found not only in nocturnal apposition eyes, but also on a smaller scale in crepuscular apposition eyes.

Controlled Replication of Butterfly Wings for Achieving Tunable Photonic Properties

The fine structure of the wing scale of a Morpho Peleides butterfly was examined carefully, and the entire configuration was completely replicated by a uniform Al(2)O(3) coating through a low-temperature ALD process. An inverted structure was achieved by removing the butterfly wing template at high temperature, forming a polycrystalline Al(2)O(3) shell structure with precisely controlled thickness. Other than the copy of the morphology of the structure, the optical property, such as the existence of PBG, was also inherited by the alumina replica. Reflection peaks at the violet/blue range were detected on both original wings and their replica, while a simple alumina coating shifted the reflection peak to longer wavelength because of the change of periodicity and refraction index. The alumina replicas also exhibited similar functional structures as waveguide and beam splitter, which may be used as the building blocks for photonic ICs with high reproducibility and lower fabrication cost compared to traditional lithography techniques.

Effects of diet and metamorphosis upon the sterol composition of the butterfly Morpho peleides

Whole body sterol metabolism in insects has seldom been studied. We were able to design an appropriate study at a butterfly farm in Belize. We collected six larvas of butterfly (Morpho peleides), their food (leaves of Pterocarpus bayessii), and their excretions. In addition, six adult butterflies were collected. The sterols of the diet, the larva, and adult butterfly were analyzed by gas-liquid chromatography. The structures of these sterols were identified by digitonin precipitation, GC-MS, and NMR. Four sterols (cholesterol, campesterol, stigmasterol, and sitosterol) and a sterol mixture were found in the food, the body, and the excreta of the larva. The tissue sterol content of the larva was 326 microg. They consumed 276 microg of sterols per day. Their excretion was 185 microg per day as sterols. The total tissue sterol contents of the larva and butterfly were similar, but they had different sterol compositions, which indicated interconversion of sterols during development. There was a progressive increase in the cholesterol content from larva to butterfly and a decrease in the content of sitosterol and other plant sterols, which were likely converted to cholesterol. Our data indicated an active sterol metabolism in butterfly larva. Diet played an important role in determining its sterol composition. During metamorphosis, there was an interconversion of sterols. This is the first paper documenting the fecal sterol excretion in insects as related to dietary intakes.

The predominance of polyunsaturated fatty acids in the butterfly Morpho peleides before and after metamorphosis

We hypothesized that the polyunsaturated fatty acids of the butterfly were probably derived from the diet and that there might be a great loss of body fat during metamorphosis. To substantiate these hypotheses, we analyzed the fatty acid composition and content of the diet, the larva, and the butterfly Morpho peleides. Both the diet and the tissues of the larva and butterfly had a high concentration of polyunsaturated fatty acids. In the diet, linolenic acid accounted for 19% and linoleic acid for 8% of total fatty acids. In the larva, almost 60% of the total fatty acids were polyunsaturated: linolenic acid predominated at 42% of total fatty acids, and linoleic acid was at 17%. In the butterfly, linolenic acid represented 36% and linoleic acid represented 11% of total fatty acids. The larva had a much higher total fatty acid content than the butterfly (20.2 vs. 6.9 mg). Our data indicate that the transformation from larva to butterfly during metamorphosis drastically decreased the total fatty acid content. There was bioenhancement of polyunsaturated fatty acids from the diet to the larva and butterfly. This polyunsaturation of membranes may have functional importance in providing membrane fluidity useful in flight.

Efficiency of fruit juice feeding in Morpho peleides (Nymphalidae, Lepidoptera)

We have described the feeding behavior of the frugivorous butterfly Morpho peleides (Butler 1872) under various conditions and tested its ability to take up fluid from selected natural and artificial food sources in comparison with the nectarvorous Vanessa cardui (Linnaeus 1758). Both nymphalids showed similar probing behavior except for one particular proboscis movement and the fact that M. peleides was unable to feed from Lantana flowers. In 2-min feeding trials, M. peleides imbibed a greater amount of fluid from the food sources, with the most conspicuous difference on rotting banana. Without time restriction, M. peleides gained a significantly greater percentage of body weight from soaked plotting paper, whereas no significant difference occurred from tubular artificial flowers. The ability of M. peleides to feed more efficiently from wet surfaces than V. cardui is discussed in context with proboscis morphology.

Butterfly Eye-spots and Corneal Reflections

The wings of the order Lepidoptera (butterflies and moths) demonstrate many interesting optical principles. Within the 165,000 species identified to date are combinations of colours and patterns that would impress the most sophisticated of art critics. The patterns and colours are achieved by the precise placement of both pigmented and non-pigmented scales which take advantage of light absorption, diffraction and scattering. For example, the colour white in the centre of the pattern in Fig. 1 is from light scattering, produced by air spaces within the scales, whereas the brilliant iridescent blues of the wings of the Morpho peleides are due to light diffraction. Of all the fascinating aspects of the butterfly patterns, that of the 'eye-spot' entices me most as an ophthalmologist. Experiments using birds and butterflies with eye-spots have demonstrated that when the peacock butterfly, Nymphalis io, suddenly displays its eye-spots by raising its hindwings and retracting the fore wings, attacking birds draw back. When the eye spot pattern is rubbed off the butterfly wings by the experimenter, the birds attack and eat the butterflies [1, 2]. One of the interesting subtleties of the eye-spot is

The demography of a confined population of the butterfly Morpho Peleides during a tropical dry season

(1974). The demography of a confined population of the butterfly Morpho Peleides during a tropical dry season. Studies on Neotropical Fauna: Vol. 9, No. 1, pp. 1-34.