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I found this moth sitting on a flower of mine in northwestern Indiana. Anyone know what species this is?
Peppered moth evolution
The evolution of the peppered moth is an evolutionary instance of directional colour change in the moth population as a consequence of air pollution during the Industrial Revolution. The frequency of dark-coloured moths increased at that time, an example of industrial melanism. Later, when pollution was reduced, the light-coloured form again predominated. Industrial melanism in the peppered moth was an early test of Charles Darwin's natural selection in action, and remains as a classic example in the teaching of evolution.   In 1978 Sewall Wright described it as "the clearest case in which a conspicuous evolutionary process has actually been observed."  
The dark-coloured or melanic form of the peppered moth (var. carbonaria) was not known before 1811. After field collection in 1848 from Manchester, an industrial city in England, the frequency of the variety was found to have increased drastically. By the end of the 19th century it almost completely outnumbered the original light-coloured type (var. typica), with a record of 98% in 1895.  The evolutionary importance of the moth was only speculated upon during Darwin's lifetime. It was 14 years after Darwin's death, in 1896, that J.W. Tutt presented it as a case of natural selection.  Due to this, the idea widely spread, and more people believed in Darwin's theory.
Bernard Kettlewell was the first to investigate the evolutionary mechanism behind peppered moth adaptation, between 1953 and 1956. He found that a light-coloured body was an effective camouflage in a clean environment, such as in Dorset, while the dark colour was beneficial in a polluted environment like in Birmingham. This selective survival was due to birds which easily caught dark moths on clean trees, and white moths on trees darkened with soot. The story, supported by Kettlewell's experiment, became the canonical example of Darwinian evolution and evidence for natural selection used in standard textbooks. 
However, failure to replicate the experiment and criticism of Kettlewell's methods by Theodore David Sargent in the late 1960s led to general skepticism. When Judith Hooper's Of Moths and Men was published in 2002, Kettlewell's story was more sternly attacked, accused of fraud, and became widely disregarded. The criticism became a major argument for creationists. Michael Majerus was the principal defender. His seven-year experiment beginning in 2001, the most elaborate of its kind in population biology, the results of which were published posthumously in 2012, vindicated Kettlewell's work in great detail. This restored peppered moth evolution as "the most direct evidence", and "one of the clearest and most easily understood examples of Darwinian evolution in action". 
Show/hide words to know
Camouflage: use of colors and patterns to blend into the surrounding area in order to hide. more
Lichen: a living organism that is not a plant or an animal. Lichens usually have two living organisms, fungus and algae that work together in a beneficial manner. more
Natural selection: the process by which individuals with certain traits survive better or worse and reproduce with more or less success than others in certain conditions. A major mechanism of evolution. more
Rural: an area outside cities and towns that is often less populated and has a lot of plants and animals.
Soot: a black powder produced by burning coal, wood, or some other substances.
Urban: an area where many people live and work together, such as a city or town. more
DNA analysis reveals butterfly and moth evolutionary relationship
Morpho didius – Museum specimen. Credit: Wikipedia
(Phys.org) —A pair of researchers with the Florida Museum of Natural History at the University of Florida has conducted a through genetic analysis of butterflies and moths and in the process has revealed some of their evolutionary history. In their paper published in Proceedings of the Royal Society B: Biological Sciences, Akito Kawahara and Jesse Breinholt describe the DNA analysis they undertook of the insects and the results they found in doing so.
Butterflies and moths are among the most cherished of insects, the researchers note, due to their beauty and relationship to equally lovely flowers. All told there are approximately 160,000 known species of the insect, though many more have not been identified—some scientists suggest there could be half a million. Despite their widespread popularity, the evolutionary relationship between the two (moths and butterflies) has been difficult to estimate—very few fossils exist due to their extremely fragile body and wing structures and the lack of thorough DNA studies. In this new effort, the team in Florida set out to more firmly establish the evolutionary tree of the wispy creatures.
The two researchers sequenced almost 3000 genes creating in the process a dataset that included 46 taxa that combined 33 new transcriptomes with 13 genomes, expressed sequence tags and transcriptomes. They used a technique known as HaMStR (a next-generation sequencing approach) to identify 2,696 genes for inclusion into their phylogenomic analysis.
Their study showed that butterflies all share a single common ancestor and give credence to the theory that butterflies are more closely related to very small (micro) moths, rather than those of larger species, contradicting previous studies that had found the opposite to be true. More specifically, they found evidence that suggests plume and geometroid moths are likely the first relatives of butterflies. Also, the research showed that insects known as hedylids, commonly known as butterfly-moths are in fact true butterflies, not moths at all.
The overall result of the work was what the duo describe as the "first robust, transcriptome-based tree of Lepidoptera"—one that strongly contradicts the placement of butterflies in the historical context. It also provides an evolutionary framework, they note, for future research efforts—be they developmental, genomic, or ecological—for both butterflies and moths.
Butterflies and moths constitute some of the most popular and charismatic insects. Lepidoptera include approximately 160 000 described species, many of which are important model organisms. Previous studies on the evolution of Lepidoptera did not confidently place butterflies, and many relationships among superfamilies in the megadiverse clade Ditrysia remain largely uncertain. We generated a molecular dataset with 46 taxa, combining 33 new transcriptomes with 13 available genomes, transcriptomes and expressed sequence tags (ESTs). Using HaMStR with a Lepidoptera-specific core-orthologue set of single copy loci, we identified 2696 genes for inclusion into the phylogenomic analysis. Nucleotides and amino acids of the all-gene, all-taxon dataset yielded nearly identical, well-supported trees. Monophyly of butterflies (Papilionoidea) was strongly supported, and the group included skippers (Hesperiidae) and the enigmatic butterfly–moths (Hedylidae). Butterflies were placed sister to the remaining obtectomeran Lepidoptera, and the latter was grouped with greater than or equal to 87% bootstrap support. Establishing confident relationships among the four most diverse macroheteroceran superfamilies was previously challenging, but we recovered 100% bootstrap support for the following relationships: ((Geometroidea, Noctuoidea), (Bombycoidea, Lasiocampoidea)). We present the first robust, transcriptome-based tree of Lepidoptera that strongly contradicts historical placement of butterflies, and provide an evolutionary framework for genomic, developmental and ecological studies on this diverse insect order.
Websites to publish a free chapter on?
I&rsquove written some of the Strange Biology book, and I&rsquom going to publish a chapter online for y'all to read for free.
I was hoping that I could send it to a more mainstream website (non-tumblr) as a promo for the book. I submitted it to one place but if they don&rsquot accept it, do you know of any website that would? Anything to do with biology, medicine, animals, or the weird that is big enough to be popular but open enough to accept unpaid submissions. Also, it&rsquos a little surgically graphic so maybe a darker place.
Of course I could just post it here, but then I&rsquod kind of be preaching to the choir. Either way I promise to release the chapter for free.
Jurassic World was originally slated as a movie about human-dinosaur hybrids. Enjoy these horrifyingly awesome pieces of leaked concept art from that stage of the movie&rsquos development.
The idea of human-like dinosaurs goes back as far as 1977 from Carl Sagan&rsquos book The Dragons of Eden. In it he asked, if the group of dinosaurs troodontids were so smart, would they have achieved a human-like level of sentience if they had not gone extinct?
In 1982 Ron Séguin and Dale Russel constructed a hypothetical troodontid with a brain proportionally similar to that of a human. They argued that the &ldquodinosauroid&rdquo should be upright, tailless, and plantiograde, but that idea has been criticized as anthropocentric.
(I might do a longer post on this later)
As a thank-you for following, and to try to entice anyone else to buy the book, here is a free chapter of Strange Biology: On Anomalous Animals, Mutants, and Mad Science! Feel free to reblog and repost anywhere for free, so long as you&rsquove got the kickstarter link. You can also share it very easily, with buttons at the end of this permalink.
Thanks again, and enjoy the chapter! But before you do, please be advised that this article contains disturbing themes, especially for dog lovers like myself, and is presented for the purpose of reviewing history.
Where Brodyaga goes, Shavka goes.
Brodyaga was a stray, his name meaning &ldquoTramp.&rdquo He had the misfortune of becoming one of the hosts for a &ldquotwo-headed dog.&rdquo This was part of a series of two-headed dog experiments executed by Soviet scientist Dr. Vladimir P. Demikhov. Shavka was a smaller dog, whose head and upper-body were transplanted onto the shoulders of her counterpart.
Shavka and Brodyaga represent one of twenty such experiments. The Russian surgeon had grafted twenty upper-bodies of small dogs or puppies onto twenty larger dogs. At the longest, one pair lived for twenty-nine days. Most lived closer to a week.
While it appears that the team had mastered stitching things together, and the extra head had sufficient circulation from the host, what ultimately did in most of his subjects was the problem of tissue rejection. Each body would recognize the other&rsquos blood as foreign and try to fight it. Today we know that we must use immunosuppresants like Cyclosporine to limit the risk of tissue rejection.
Before their surgery, the medical staff put both dogs under anaesthetic. The doctors shaved the dogs where they would be cut Brodyaga on his neck and Shavka in her middle, to be bisected. Demikhov and his team cut into Brodyaga&rsquos neck to expose his aorta, jugular vein, and a neck vertebrae. They wrapped most of Shavka in a towel, exposing her midsection, and the team slowly, carefully cut into her, layer by layer. With great care, they attached Shavka&rsquos smaller blood vessels to Brodyaga&rsquos, and then they severed her spine behind her shoulders. They removed most of her body and set it aside. The staff connected Shavka&rsquos remaining main blood vessels to Brodyaga, and then attached her trachea to his lungs. Shavka&rsquos own heart and lungs were then removed. Her esophagus led to the outside of their bodies.
After awaking from surgery, both dogs were able to move independently. Shavka would try to eat and drink, but she had no stomach to speak of. All her nutrients and oxygenated blood came from Brodyaga. The larger dog could walk them both around the yard, and Shavka would even bite Brodyaga on the ear.
Demikhov attended the University of Moscow in 1934 to study biology. In 1937 he designed the world&rsquos first &ldquosuccessful&rdquo cardiac assist device. No one else had ever able to sustain the pulse of an animal with its heart removed before Demikhov, but his device kept a dog alive for five hours. He served as a pathologist in World War II, where he honed his skills as a surgeon. In 1946 he resumed his experiments on dogs. In these experiments, Demikhov performed the first successful transplants of hearts, lungs, and heart-lung sets in any mammal. In spite of his enormous contributions to both organ transplantation and the creation of artificial hearts, none of his work gained the fame that the two-headed dog did. In 1989, after performing the vast majority of his research in comparative obscurity, he received the International Society for Heart and Lung Transplantation&rsquos Pioneer Award. In 1998 he was paralyzed from recurrent strokes, and he died in his apartment.
Demikhov&rsquos experiments, however preternatural, were in fact instrumental in transplant science. In general he focused on putting organs such as hearts and lungs into dogs, and by the time of his death, his contributions to medical science were standardized into medical school curriculum. In 2004 alone, over 3,000 people worldwide received heart, lung, or heart-and-lung transplants. Although, not all people survive for very long afterward only 10% of heart recipients live for 10 years after. But even these successes would be impossible if Demikhov or someone else had not had the initial gusto to do the experiments on animals. Ideally the survivorship rates will only increase as we hone techniques, decrease tissue rejection rates, and improve the technology.
Surely the heart and lung transplants were important, but was it really necessary to create a real-life Cerberus? It&rsquos hard to say. The Soviet Union at the time was very much interested in work that they could tout as testament to their superiority, and it&rsquos possible that they saw transplant science as a potential boon to Russian propaganda. A dog with two-hearts isn&rsquot much of a thrill for a freakshow, and it&rsquos likely that they wanted something they could flaunt internationally.
The landmark Animal Welfare Act of the US wasn&rsquot passed until 1966, and to this day there is no animal welfare legislation in Russia. Even so, people were concerned for the lives of the animals involved in Demikhov&rsquos transplant experiments. In the 1950s a review committee of the Soviet Ministry of Health was so perturbed by these acts that they demanded that the doctor discontinue immediately. However, Demikhov was at the time working at the Moscow Institute of Surgery, the director of which was not subject to the review committee.
One of Demikhov&rsquos more horrific experiments involved severing the back half of two dogs and swapping them for example, one yellow dog with a black backside, and one black dog with a yellow backside. As he could not reattach the spinal columns, none of these dogs were able to use their back legs, and these experiments went nowhere.
There is no denying that these animals suffered and their premature deaths were tragic. These days Demikhov&rsquos experiment proposals would have to pass an ethics committee, and it&rsquos unlikely that he would have received funding, especially not in the U.S. People still test on animals for the purposes of understanding biology, psychology, medicine, and even (less justifiably), cosmetics in some countries.
It&rsquos easy to say these experiments were just dime-museum attractions since they didn&rsquot directly lead anywhere. Human head transplants are not (yet) a reality in the medical community, and have yet to save any lives. But it is important to remember that most experiments go nowhere. That doesn&rsquot mean they were useless. The strange transplants that Demikhov performed taught us that these things are in fact possible, and if done right, perhaps one day they could come into use. The experiments also teach us how difficult transplantation is, and to take that into consideration in the cases of modern head transplant research. That&rsquos how science is you might risk your money, name, and reputation for the greater good, or you might lose it for nothing at all.
Demikhov was not the last person to do head transplantation, and he was not the first either. In 1908 Dr. Charles Guthrie did a similar experiment. He also attached two dogs together, so that they were in the position of chin-to-chin. However, so much time had elapsed between the severing of one head and the attachment to the other body that the attached dog didn&rsquot retain much brain function outside of basic reflexes.
In 1959, Chinese scientists claimed that they had transplanted one dog&rsquos head onto another&rsquos body, twice. In 1970 a group of American scientists grafted the head of one rhesus monkey onto the headless body of another. In 2002, researchers in Japan attached second heads onto mice, working in low temperatures to prevent neurons from dying after being severed from their oxygen supply.
The American scientists, led by Dr. Robert White, were the first to successfully transplant a mammalian head from one body to another headless one. These monkeys were able to move, bite, and even try to eat, although their esophagus was not attached to anything so they couldn&rsquot swallow. The longest one lived was eight days. White speculated that head transplants could extend the lives of quadriplegics. Often people paralyzed from the neck down die early due to organ failure. If their heads were successfully transplanted onto a functional donor body, that could improve their survival rate.
In 2013, Dr. Sergio Canavero announced that he planned to do the first human head transplant at some point. With the use of fusogens, he argued, he would be able to re-attach a severed spinal cord, giving complete control of a functional body to a former quadriplegic with organ failure.
Dr. Demikhov had visions of transplants galore. Imagine if your body was failing, and you would be able to make use of one of the many cadavers that turn up in hospitals and morgues daily. If transplantation worked universally and without complication, it could be a panacea of medicine. How rarely would one have to live with missing limbs, or blindness, or general organ failure. You could replace your whole body when it got old, so long as there were enough dead people around to provide healthy tissue.
There is a Russian proverb that means that adversity is a good teacher. &ldquoБез муки нет науки&rdquo literally translates to &ldquoWithout torture, no science.&rdquo People who benefit from organ transplants may agree. The dogs might not.
Wherever Brodyaga went, Shavka went. Four days after the operation, one of the neck veins connecting them was strangled, and in the night they both went to their deaths together.
Codling Moth Biology
Codling moth is a key pest in apple, pear, crabapple, and Oriental pear trees. The adult codling moth is a small, brown and gray banded moth about 1⁄2 inch long (Figure 1). Difficult to scout for as these moths fly during dusk and dawn, but they can be monitored with traps baited with pheromone lures.
After mating, one female moth lays dozens of flat, circular, 1/12-inch (or 1 mm) diameter eggs in a tree (Figure 2). Again, it is difficult to scout for the eggs as they are tiny and often match the surface color of the apple. These eggs hatch into larvae or “worms” looking for fruit to bore into and call home.
When they find such a fruit, the worms bore directly to the core of the fruit and feed about the seeds (Figure 3). Their feeding activities result in conspicuous piles of brown, granular piles of excrement (frass) plugging the entrance hole on the surface of the fruit (Figure 4). While this is the easiest sign of codling moth to scout for, once larvae enter the fruit they can only be controlled by picking and disposing of the fruit. Mature worms can be up to 3/4 inch long caterpillars, and often have a pinkish cast.
When mature, the worms leave and drop from the fruit to pupate in cocoons at the base of the tree. Often they pupate among the cracks and crevices of the tree bark, but they will pupate in any nook or cranny on wooden structures, posts, firewood piles, crates, and even furniture near the host tree.
Washington homeowners must protect their apple/pear fruit from two, sometimes three in the warmer regions of the state, generations of codling moth each year. The adult moths fly during warm evenings with peak flight activity in May, July, and late August. The best means of protecting backyard fruit trees from codling moth attack is an integrated pest management (IPM) program utilizing several control strategies.
Life Cycle of Silkworm Moth
The adult moths are 25 mm in length and the span of wings is 40-50 mm. The female silkworm moths are larger than the males. The univoltines are larger than the multivoltines. Usually whitish in colour and in some forms specially the males have grey marks on their wings. The body is distinctly divisible into three tagmata—head, thorax and abdomen.
The head contains distinct eyes and feathery antennae, the latter being larger in males. Three pairs of legs and two pairs of wings are present in the thoracic region. Female moths do not have any mouth. They rarely move. Internally, the body contains well-developed excretory and reproductive systems.
The digestive system is poorly de­veloped. The excretory organs are three pairs of Malpighian tubules. There are three such tubules on each side. A duct from each side unites together to form a common tube which opens into the stomach at its posterior end. In males, the paired testes are lodged within a capsule.
From each testis originates a duct, called vas deferens, which inflates immedi­ately after its origin to form a seminal vesicle. Posteriorly the two vasa deferentia unite to form a much coiled ejaculatory duct which opens to the exterior through the genital opening. In the female, each of the paired ovaries contains four egg tubes.
From each ovary arises an oviduct the two oviducts unite to form a common oviduct. There are two female genital apertures—through one opens the oviduct and through the other communi­cates a large sac-like copulatory pouch. A short tube links the pouch with the oviduct. This tube is called seminal duct.
A portion of it is dilated to act as spermatheca. Both the sexes are provided with accessory glands which open within the genital ducts. A scent gland is present at the terminal end of the female abdominal cavity. Its secretion attracts the males of the same species. During copula­tion, the male sits on the back of the female and grips it tightly by its chitinous hooks.
Such pairing lasts for three hours. This is immediately followed by egg lying. The sperms enter through a small opening on the egg, called the micropyle. But the actual fusion of male and female pronuclei occurs two hours after lying. Parthenogenesis, i.e., development of egg without the participa­tion of sperm, is also common in silkworm moth.
Stage # 2. Eggs:
The colouration, size and weight vary in different species. The eggs are small, oval and usually slightly yellowish in colour. The egg contains a good amount of yolk and is covered by a smooth hard chitinous shell. Approximately 500 eggs are laid in 24 hours.
In some forms the eggs are glued on the surface of the leaf by a product secreted from a special gland. The univoltine broods hatch after one year but the multivoltine broods come out after 10-12 days. From the egg hatches out a larva, called caterpillar, which has no resemblance to the adult.
Stage # 3. Larva:
Each larva is 3 mm in length and is provided with a thick hairy covering (Fig. 18.82A). The colour is usually greyish brown but the colouration changes in course of development. The larva possesses a promi­nent head, distinctly segmented thorax and elongated abdomen. A conspicuous crescent spot is present on the dorsal side of the sixth segment.
The head is formed by the fusion of three segments. At the anterior end a triangular area is formed by a pair of oval lobes. The mouth parts include a pair of strong mandi­bles, a pair of lips, a pair of maxillae and two pairs of maxillary and labial palps. The head also bears a pair of antennae and six pairs of ocelli. A distinct hook-like structure, the spin­neret, is present for the extrusion of silk from the inner silk gland.
Each of the three thoracic segments bears a pair of legs having three articulations. The tip of each leg has a recurved hook for locomotion and ingestion of leaves.
The abdomen is divisible into ten seg­ments of which the first nine are clearly marked while the tenth one is indistinct. The third, fourth, fifth, sixth and ninth abdomi­nal segments bear abdominal appendages, called false legs. Each leg is retractile and more or less cylindrical.
The body of the caterpillar contains fol­lowing internal structures (Fig. 18.82B):
The alimentary canal is prominent and includes a short oesophagus, a spacious stomach, much coiled and long intestine and a swollen rectum. A pair of salivary glands opens by a common salivary duct to the mouth cavity and serves as a digestive gland.
Tracheal trunks open to the exterior by nine pairs of spiracle. First pair are present on the first thoracic segment and remaining pairs are situated on the first eight abdominal segments.
The heart is present immediately above the alimentary canal along the mid-dorsal line of the body cavity. It is a transparent contractile tube, also known as the dorsal vessel. The blood is usually colourless but may be pink or green. The colour of the silk depends upon the colour of the blood.
The nervous system includes a pair of cerebral ganglia as brain and a paired ventral nerve cord carrying twelve ganglia in its path. The sense organs are present as six pairs of ocelli for detecting light and numerous sensory receptors on the maxillary and labial palps.
These unique and con­spicuous glands are paired structures, which are present in the fourth to eighth segments of the larva. When fully formed each gland becomes five times the length of the larva and its weight becomes two-fifths of the body weight. Each gland is divisible into three sections—the anterior, middle and posterior (Fig. 18.83).
The middle part is broad and called the reservoir. The anterior and posterior parts are pointed at their two ends. The two anterior ends of the glands unite to form a common duct which opens through a spinneret. The posterior part pro­duces a protein, called fibroin, around which the middle part puts an envelope, called sericin.
The silk is released in a liquid state, which soon hardens. A pair of accessory glands, called the glands of filippi or Lyononet’s glands, open into the duct of the silk gland. The secretion of this gland mixes with that of the silk gland and probably lubricates the inner and outer cores of the silk.
(6) Reproductive system:
The reproduc­tive organs are very minute and their ducts are indistinct.
Transformation of larva:
The larva is a voracious eater. In the beginning, chopped young mulberry leaves are given as food, but with the advancement of age entire and matured leaves are provided as food. The routine of caterpillar includes only two ac­tivities—eating and sleeping. It grows fan­tastically and increases, 10,000 times in weight from newly hatched state.
Such growth in­volves the consumption of mulberry leaves which are 30,000 times more than its body weight. The growth requires the replacement of exoskeletal covering and the larva within its 30-40 days life does the same for four times. Such removal of the old exoskeleton is known as moulting.
At the time of moulting, the larva does not take any food and places its head upwards. This phase is very critical in the life of larva. At the end of fourth moult a fully formed larva with matured silk gland becomes transparent and golden brown in appearance. At this stage the larva ceases to eat and starts spinning silk around its body from outside to inside (Fig. 18.84).
In order to make a complete covering the larva ro­tates 60,000 to 3,00,000 times and the silk is liberated at the rate of 15 cm per minute. This covering, called the cocoon, is formed of a continuous silken thread of 400-1500 metres long.
The caterpillar takes 3-4 days to com­plete a cocoon within which the larva, now known as pupa, remains completely immo­bile. A cocoon may be of varied shapes and colours. The cocoon formed by a male silkworm moth is lighter in colour than that of a female and contains more silk.
Stage # 4. Pupa and Imago:
It is covered by a hard shell. It generally remains immobile, but can change its position by the contractile movement of the last few abdominal segments. Within the pupa, considerable activity takes place. The old structures of pupa are broken down by a process, called histolysis, and new parts of the adult are prod iced.
Gradually within the cocoon, pupa transforms into a stage, called imago. For the purpose of breaking the co­coon, the imago liberates a fluid which dis­solves the covering at one end. The emer­gence of adult takes place after 10 days of pupal life (Fig. 18.85).
Weird & Wonderful Creatures: Giant Leopard Moth
The giant leopard moth (Hypercompe scribonia) grows from a red-striped "woolly bear"-type caterpillar to a white-spotted moth large enough to fit comfortably in an adult's hand.
As an adult, the moth is noteworthy in its appearance: Its wings are bright white, with a pattern of black and shiny blue dots (some solid and some hollow) sprinkled across them. It has a wingspan of three inches, and when its wings are spread, you can see its colorful abdomen: The top side is iridescent blue with orange markings, while the underside is white with solid black dots. Its legs have black and white bands. Male moths (they have a yellow band along the side of their abdomens) are approximately two inches long, while females grow to slightly more than half that size.
As a caterpillar, the giant leopard moth grows to approximately two inches long and has shiny black bristles covering its body. Unlike some other "hairy" creatures, these caterpillars' bristles are not urticant, which means that they don't break off in predators when touched, causing irritation and discomfort. Because the giant leopard moth's bristles do not cause this reaction, it's okay to gently touch the caterpillar. If you do, it may react by curling up in a ball, which will let you see the red or orange bands between its body segments. The caterpillar will hibernate over the winter in this form and will spin itself into a cocoon in the spring.
"Giant Leopard Moth caterpillar (Hypercompe scribonia)." Photo Credit: Aaron Carlson. Licensed under CC BY-SA 2.0, via Flickr.
The caterpillar eats a variety of broad-leafed plants, including violets, sunflowers, basil, dandelions, and lettuce, as well as a leaves from a number of trees, including willows, mulberries, maples, and cherries.
The giant leopard moth can be found across fields, meadows, and forest edges of eastern North America and as far south as Colombia in South America. It is nocturnal, flying only at night, and adults can be seen between April and September. When handled or threatened, it may release drops of foul-tasting yellow fluid from its thorax to ward off predators.
If you think moths are interesting, you can sign up for and participate in National Moth Week, July 23–31, a citizen science activity. You can read more about it in this blog post from 2014. You can also check out the Journey North App, which can help you track moths' and other animals' migrations and seasons, and Nowhere to Hide, a Flash-based interactive that demonstrates the story of the peppered moths in England during the Industrial Revolution. Scientists recently found the gene that explains their story.
Do you think butterflies are cooler than moths? Learn more about them in the Butterfly 1: Observing the Life Cycle of a Butterfly and Butterfly 2: A Butterfly's Home lessons for grades K-2.
Did you know that a cocoon and a chrysalis are not the same thing? You can find out what the difference is here.
- The ‘miller moth,’ common in Colorado and adjacent states, is the adult stage of the army cutworm.
- The caterpillar stage of the army cutworm feeds on crops and garden plants in winter and early spring.
- The adult form of the army cutworm feeds on nectar in late spring through early fall. It does not lay eggs during this time.
- During warm months the ‘miller moths’ migrate to higher elevations as they seek flowering plants. Areas close to the mountains
receive moths that may have migrated well over a hundred miles en route to summer feeding sites.
Figure 1: Army cutworm moth. (Photo courtesy of J. Capinera.)
Figure 2. Army cutworm with damaged seedling.
Figure 3. Army cutworm pupa. (Photo by W. Cranshaw.)
Figure 4. Army cutworm moths showing variable patterning. (Photo by W. Cranshaw.)
‘Miller moth’ is the term given to any type of moth that is abundant in and around homes. In Colorado and much of the Rocky Mountain west, the common ‘miller’ is the adult stage of the army cutworm, Euxoa auxiliaris. In some years it becomes a serious nuisance pest, particularly during its annual migration from the plains to the mountains in late spring.
Army cutworm moths have a wing span of 1.5 to 2 inches. It is generally gray or light brown with wavy dark and light markings on the wings. The wing patterns of the moths are variable in color and markings, but all have a distinctive kidney-shaped marking on the forewing.
Severe nuisance problems with “millers” seem to be limited to eastern Colorado. However, army cutworms also occur in western Colorado and may be an important crop pests in late winter and spring. Adults similarly migrate to the mountains to spend the summer but less frequently occur as serious nuisance pests along the West Slope.
Life History and Habits
The army cutworm has an unusual life history. Eggs are laid by the moths in late summer and early fall. Most eggs are laid in weedy areas of wheat fields, alfalfa fields, or other areas where vegetation is thick—including turfgrass. Eggs hatch within a few weeks and the young caterpillars begin to feed. Army cutworm has a wide range of plants on which it feeds. It prefers broadleaf plants but will also feed on grasses.
Army cutworms spend the winter as a partially grown caterpillar, feeding as temperatures allow. In early spring the cutworms may damage crops, particularly alfalfa and winter wheat. They may also damage garden plants and are common in lawns. When high populations occur that consume all plants they may take on the “armyworm” habit of banding together crawling across fields or highways. Army cutworms become full grown by mid-spring, burrow into the soil, and pupate. Pupation can occur as early as March or may extend into early May, depending on temperatures.
Between three to six weeks later, the adult “miller” stage of the insect emerges. Next, they migrate and ultimately settle at higher elevations where they spend a few months, feeding on nectar and resting in sheltered areas. During this time they are in reproductive diapause, a physiological state during which they do not produce nor lay eggs. In early fall or late summer, they return to lower elevations, come out of diapause, and begin to lay eggs, repeating the annual, single generation life cycle.
Miller Moth Migrations
Miller moths are the migrating adult stage of the army cutworm. In eastern Colorado, spring flights move westward, originating from moths that developed across eastern Colorado and border areas of Wyoming, Nebraska, Kansas, and Oklahoma where army cutworm also occurs.
A likely explanation for the migration is that it allows the moths a reliable source of summer flowers. Flowers provide nectar which the moths use for food. In addition, the cooler temperatures of the higher elevations may be less stressful to the moths, allowing them to conserve energy and live longer.
During outbreak years, miller moth flights typically last five to six weeks, generally starting between mid-May and early June. However, they tend to cause most nuisance problems for only two to three weeks.
Exactly when the flights occur and for how long varies. During the 1991 outbreak high populations were present from early May through mid-June. However, in 1990, a year that also was above average for miller flights, heavy flights were not noted until early June and lasted about a month. In the warm, dry 2002 season, nuisance numbers of miller moths along the Front Range occurred over a very extended period—from late April through early July—and were concentrated around irrigated areas due to the drought.
Miller moths avoid daylight and seek shelter before day break. Ideally, a daytime shelter is dark and tight. Small cracks in the doorways of homes, garages, and cars make perfect hiding spots. Often moths may be found clustered together in particularly favorable sites. Since cracks often continue into the living space of a home (or a garage, car, etc.) a ‘wrong’ turn may lead them indoors. At night, the moths emerge from the daytime shelters to resume their migratory flights and feed.
The return flights (mountains to the plains) in early fall usually span a shorter period of time, typically beginning in the latter half of September. However, since the majority of moths die during the summer the return flight is less obvious.
The number of miller moths in late spring is primarily related to the number of army cutworm caterpillars which occurred earlier in the season. Outbreaks of the army cutworm are usually followed by large flights of miller moths.
Many things influence cutworm outbreaks. Wet weather and extremely cold winter conditions may kill many of the caterpillars. The effectiveness of natural enemies, such as ground beetles and parasitic wasps, help regulate cutworm populations. Plowing fields where cutworms develop kills many, as does tilling gardens.
Miller moths may concentrate around buildings more intensively during some years. The presence of flowering plants and local humidity conditions are suspected as being important in concentrations of miller moths. This effect is seen particularly during drought years when there are few natural sources of flowering plants at lower elevations. The presence of certain highly favored flowering plants, notably Russian olive, is frequently associated with localized nuisance problems.
Damage by Miller Moths
The caterpillar stage of the army cutworm is sometimes an important crop pest in the spring. For example, during outbreak years thousands of acres of alfalfa, winter wheat, and other crops are treated with insecticides for army cutworm control (See fact sheets 5.577, Caterpillars in Small Grains and 5.565, Caterpillars in Field Crops: III.). Army cutworms are also common early season pests of gardens and feed on lawn grasses along with sod webworms and other cutworms.
However, the adult miller stage is primarily a nuisance—albeit a considerable nuisance at times. Moths in the home do not feed or lay eggs. During the migratory flights, the moths do not produce nor lay eggs. Furthermore, they do not feed on any household furnishings or food. Moths in the home will eventually find a way outdoors or die without reproducing.
When large numbers die in a home there may be a small odor problem (due to the fat in their bodies turning rancid). Also, unless they are cleaned out, old moths may serve as food for carpet beetles (See fact sheet 5.549, Carpet Beetles.) and other household scavengers. These secondary insects may become problems in subsequent years.
Miller moths also may spot drapes or other surfaces, such as unfinished wood because they excrete fluid for most of their adult life. This product is slightly acidic and is sprayed by the moth. Presumably the purpose of this is defensive, although it is not particularly irritating.
Probably the greatest damage created by millers is the lost sleep resulting from their flying about the room and the needless worry that they may reproduce in the home and cause harm to household furnishings.
Figure 5. Miller moth feeding at a flower. (Photo by W. Cranshaw.)
Natural Enemies of Miller Moths
The caterpillar stage of the army cutworm has many natural enemies. Predatory ground beetles, and many birds eat cutworms. Adult millers may be eaten by bats or birds.
One commonly observed phenomenon involving birds is swallows concentrating at intersections where they feed on miller moths. (House sparrows and other birds also are found at these sites, feeding on wounded moths.) This likely occurs because many miller moths seek shelter in automobiles and emerge while the cars are idling at stop lights. Furthermore, many moths are released as drivers open vehicle windows at intersections to let the moths escape.
Other wildlife feed on miller moths as well. For example, they can be an important part of the grizzly bear’s diet in the Yellowstone National Park area. Grizzly’s feed on the fat-rich moths that rest under loose rocks.
However, factors that determine the abundance of miller moths from season to season are largely unknown. Undoubtably certain weather patterns have a great effect.
Miller Moth Control Around Homes
Before miller moth migrations, seal any obvious openings, particularly around windows and doors. Also reduce lighting at night in and around the home during flights. This includes turning off all unnecessary lights or substituting non-attractive yellow lights.
Landscaping may affect the number of millers you’ll see because it may provide food (nectar) and/or shelter. Some of the flowering plants most readily visited by miller moths along the Front Range include lilac, cherries, spirea, cotoneaster, horsechestnut, raspberry, and Russian olive. Dark, dense plants such as cotoneaster shrubs, spruce, and pines will be used most often as shelter by miller moths. Landscaping considerations can be important in the tendency of miller moths to linger around a home.
Once in the home, the best way to remove the moths is to swat or vacuum them, or attract them to traps. An easy trap to make is to suspend a light bulb over a bucket partially filled with soapy water. Moths attracted to the light often will fall into the water and be killed. (If this is attempted some wetting agent, such as soap or detergent, must be added or many moths will escape. Also, there are obvious dangers when bringing water and electrical equipment in close proximity and great care should be given to the situation. This includes use of a GFI receptacle for safety.)
Figure 6: Indian meal moths cause problems on dried food products in the home. Adult and larvae shown.
Figure 7: Casemaking clothes moths: adult and webbing.
Army cutworm moths are very sensitive to certain noises, making erratic flying movements in response. Among the sounds which elicit greatest response are jingling keys, dog tags, rattling coins, and crumpled pop cans. The likely reason for this is that certain sound frequencies are produced to which the moths are sensitive. Many cutworm moths make evasive movements in response to frequencies used by bats during echolocation of prey. Since bats are an important predator of night flying moths, rapid evasive movements are a means of protection. Regardless, jingling keys or making similar noises can disturb many of the moths in the home causing them to seek shelter and can sometimes dramatically speed the capture rate when using the soapy water trap.
Insecticides have little or no place in controlling millers. The moths are not very susceptible to insecticides. Furthermore, any moths killed will be rapidly replaced by new moths migrating into the area nightly.
Other Moths Common in Homes
The most common moth found in Colorado homes is the Indian meal moth. Adults are much smaller than the miller moth, about 1/2 inch, is yellow brown with a dark tip on the wing. The caterpillars of the Indian meal moth develop in various cereal products, nuts, dried flowers, and other stored foods. Information on the Indian meal moth can be found in fact sheet 5.598, Indian Meal Moth.
Clothes moths are very rare in Colorado, but can occur when infested woolen items are introduced into a home. It is a very pale colored moth even smaller than the Indian meal moth. They are rarely observed flying and do so only when dark.
* Colorado State University Extension entomologist and professor, bioagricultural sciences and pest management. 5/03. Revised 7/14.
Coevolution between Predator and Prey
That brings us to our second important biological concept displayed by this system: Predator-prey coevolution.
Coevolution is a process through which two or more species actively affect one another’s evolutionary trajectory. In simple terms, bats and moths are evolving together based on the adaptations each group evolves!
Long before the first bats, insects likely had total dominance of the skies. Ultrasonic hearing or stealthy scales were not necessary, because there were no predators chasing them in the skies. Then, birds and bats evolved. These creatures could pursue insects in the skies. That’s when the “arms race” began.
Bats, apparently in an effort to not compete with birds, evolved to become nocturnal. But, this brought up several issues. First and foremost, bats could no longer see where they were flying or what they were chasing. So, they started listening.
Over the course of millions of years, bats evolved the ability to navigate using ultrasonic sonar. The bats send out a “click” and listen for the sound waves to bounce off of solid objects. In this case, insects.
At first, the moths likely lost the battle. Without any defenses against this ultrasonic adaptation, the moths were eaten up. But, a few novel variants made it through the carnage. Moths evolved things like ultrasonic hearing and the newly discovered “stealth-scales”, that gave them a leg up in the war.
These back-and-forth adaptations are a perfect example of predator-prey coevolution, which happens between predator and prey species in all ecosystems around the globe. But, it doesn’t stop here. Moths and bats will both continue evolving traits to fight the war.
Who knows? Someday we may have bats that can kill moths with their ultrasonic clicks and moths with massive defensive scales to absorb the blows!