psocoptera metamorphosis


Douglas, in Encyclopedia of Microbiology (Third Edition), 2009. These two groups are suggested to have diverged in the late Jurassic or early Cretaceous Period, 100150 million years ago (MYA) (Lance, 2008). nathistoc uci bio orange county crustacea crayfish shrimp lobsters Although the Mallophaga group is likely paraphyletic, it is widely agreed that sucking and chewing lice originated from a common nonparasitic ancestral group closely related to the order Psocoptera (book lice and bark lice). Some booklice feed on stored grains while others are library pests. Reproduced with permission from Gillespie, R.G., Roderick, G.K., 2014. A few Psocoptera live in bird nests. There are differences in the form and chaetotaxy of the genitalia of the two races, but Ferris discusses these details and dismisses them as inconstant (Busvine, 1948). Lice are small, wingless insects that cannot live independently from their host (Weiss, 2009). Most of them live outdoors. In addition to being pests in urban and agricultural settings, and the potential for severe consequences resulting from ant invasions into natural areas is high (Krushelnycky et al., 2005). Isolation across scales of space and time. Other non-homologous M-factors no doubt exist in other fly groups [13]. For example, the spider genus Dysdera includes three well-defined lineages; for the lineages that have proliferated, diversity has arisen largely in situ (Macias-Hernandez et al., 2008). The accentuation of disharmony through speciation is well illustrated in the moth genus Eudonia, which is represented by only one species in central Polynesia and eastern Melanesia (the presumed source), but by 18 species in the Society Islands, 13 in the Marquesas, and over 100 species in Hawaii. Interestingly, both adults and larvae can spin silk from these glands. More recent studies have examined specific patterns of intra-island diversification and islandisland vicariance, as has been demonstrated for Amphiacusta crickets (Oneal et al., 2010) and Drosophila flies (Brisson et al., 2006). In M. domestica, individuals can even vary in which chromosome encodes the M-factor Mdmd has been detected on four of the six chromosomes (Y, II, III, and V) in different populations [16,22]. The cerambycid beetle Nothorrhina muricata lies in a crevice in the bark of trees and strikes the sides of this by vibrating its body rapidly, producing a purring noise (Faber, 1953). Among psocids (Insecta, Orden Psocoptera), the Archipsocidae is an especially intriguing and little known group of organisms where sociality and inbreeding appear to be associated in ways reminiscent of the social spider systems (e.g., Mockford, 1957; New, 1973). Those that do this feed on the remains of feathers or on skin cells, never on the birds themselves. Figure 2. There have been cases of serious injury from LFA stings, including blindness and anaphylactic shock. In the so-called deathwatch beetles, such as Anobium and Xestobium, noise is made only by adult beetles and is thought to be produced by striking of the wood with the lower part of the front of the head (Gahan, 1918). Although these symbioses have evolved independently multiple times between diverse groups of insects and microorganisms, the associations have three common traits. In the Canary Islands, most of the arthropod work has focused on beetles, butterflies, Drosophila, cockroaches, bees, spiders, and mites (Juan et al., 2000), with additional work on other lineages, including grasshoppers and mantids. Fig. Data from Krushelnycky et al. Those with wings are called psocids (pronounced so-sids). Thus, Rhyncogonus weevils occur on oceanic islands throughout the Pacific, and appear to have colonized archipelagoes in a sequential stepping-stone fashion (Gillespie et al., 2008). The nature of the symbionthost interactions has been inferred from the distribution of these relationships, which are particularly prevalent in insects feeding on nutrient-poor diets, such as plant sap (phloem or xylem) deficient in essential amino acids and vertebrate blood deficient in B vitamins (Table 2). Over evolutionary time in situ speciation comes to dominate over colonization as the source of new species. Some species are gregarious, living in small colonies beneath a gossamer blanket spun with silk from labial glands in their mouth. entomology wiki tutorials Remarkably, the intranuclear bacteria of N. cincticeps are transmitted paternally (i.e., from one generation to the next) via the nuclei of sperm cells [45]. P.T. In C. pulsatoria the insect has a small knob near the end of the ventral side of the abdomen with which it taps the ground; the sound is said to be confined to the female and may be a mating call (Pearman, 1928). Direct experimental evidence for the translocation of essential amino acids from bacteria to insects has been obtained for cockroaches and aphids, and the nutritional role of other symbiotic microorganisms is inferred from their complement of metabolic genes, identified either by PCR amplification or from completely sequenced genomes. The order of Phthiraptera is divided into two major groups: Anoplura (the hematophagous sucking lice of placental mammals) and Mallophaga (the chewing or biting lice of birds, marsupials and placental mammals) (Lance, 2008). These are honeydew-producing insects. There are over 1,000 species of Psocoptera in Europe, and around 100 in the British Isles. The primitive development of modern Paraneoptera is six-instar hemimetaboly as seen in most Psocoptera. Aedes Nix also encodes a potential splicing factor, suggesting this may be a common starting point for M-factors [18]. The Hawaiian Islands are characterized by some of the most remarkable examples of diversification in arthropods. But it is not the sex chromosomes themselves that define sex, but rather the sex determining signals they encode. Their stings leave painful welts on the skin that last about 2 weeks. They undergo gradual (paurometabolous) metamorphosis with the life stages are egg, nymph and adult. A fascinating element that is emerging from studies of diversification of arthropods in the Galapagaos is the pattern of repeated evolution of similar ecotypes, as illustrated by wolf spiders (De Busschere et al., 2012) and beetles (Hendrickx et al., 2015) associated with extensive admixture, the latter contributing to diversification. There is no evidence of any special organ. (2004) point out, these introduced can disrupt native food webs, either directly by depletion of particular prey species, or indirectly through competition that alters predator-prey relationships. Since the late 1970s, lice found on the head versus lice found on the body have been considered separate species (Pediculus capitis and Pediculus humanus, respectively) or subspecies of P. humanus (Busvine, 1945; Maunder, 1983), despite the fact that, under experimental conditions, the species can interbreed and produce fertile offspring (Bacot, 1916; Buxton, 1940; Maunder, 1983; Nuttal, 1919). There are no consistent points of distinctive morphology (Ferris, 1953), and identification relies only on the location on the human body surface (Maunder, 1983). These ants form supercolonies consisting of a large number of nests spread over large areas where the individuals from one nest can be brought to any other nest and accepted as nestmates. Liposcelis divinatorius is one example of a 'ticking spider' - although of course it is an insect, not a spider! They have long antennae, broad heads and 'bulging' eyes. Although they are called lice, the Psocoptera are free-living insects, not parasites. This hypothesis was refuted because this color difference is not constant as we can find gray body lice in Africa (e.g., body lice in Ethiopia) (Fig. HL: head louse, BL: body louse. Nitrogen recycling refers to the microbial consumption of animal waste nitrogenous compounds (e.g., ammonia and urea) to synthesize high-value nitrogenous compounds (e.g., essential amino acids), which are released back to the host (Figure 2). Immediately related to the nutrient provisioning is the role of microorganisms in recycling, especially of nitrogen. A pattern similar to the diversity of unrelated M-factors in Diptera may be found in Hymenoptera. Once established, Little Fire Ant (LFA) colonies can become enormous. Indoor species can be found by looking in musty-smelling, neglected corners - including, perhaps, your prized insect collection! Sex determination systems diversify rapidly among species [7]. Although a break in gene flow is clearly important for adaptive differentiation, hybridization, and genetic admixture resulting from previously separated populations coming back in contact, have increasingly been implicated in the generation of adaptive variation and functional novelty (Gillespie and Roderick, 2014; Figure 5). Texas A&M Veterinary Medical Diagnostics Laboratory, Texas A&M College of Agrculture and Life Sciences. california insects uci bio nathistoc orange county primitively edu caterpillar entomology wiki scioly thoracic abdominal fleshy cylindrical moths pairs prolegs butterflies legs short body appearance tutorials In general the substrate is the ground or the material in which the insect lives, e.g., wood; but several cases are known, some of which are mentioned below, where the insect uses its own body or that of another member of the species. (2) The microorganisms are obligately vertically transmitted, usually by insertion from the maternal bacteriocytes directly into the eggs in the female ovary. (a) On a multimillion-year timescale, distinct assemblages of biota form in isolation on different continents, and joining of the continents may lead to biotic exchange or species displacement. (H) Little fire ant. Frederik Schulz, Matthias Horn, in Trends in Cell Biology, 2015. An unusual, possible unique, method of sound production occurs in the Tenebrionid Bolitherus cornutus where, during courtship, the male rubs its abdominal sternites against two tubercles on the thorax of the female, producing a rasping noise which can be heard several feet away (Liles, 1956). In the subsequent 15 years, the species has spread to over 4000 locations on the island of Hawaii and has been found in isolated locations on Kauai, Maui, and Oahu Islands. Scott A. Elias, Nick Porch, in Reference Module in Earth Systems and Environmental Sciences, 2021. As is so often the case, wasps introduced to reduce caterpillar populations of certain species go on to attack a variety of other moth species, most of them endemic taxa whose populations are already at risk from habitat and native host plant losses. Throughout the 20th century, it has been accidentally introduced in many parts of the world by human commerce. In the termites, Emerson and Simpson (1929) showed that soldiers of Reticulitermes flavipes tapped their heads on the wood substrate and Howse (1962a) has investigated this in Zootermopsis angusticollis. Psocoptera are regarded as the most primitive amongst the hemipteroids (true bugs, the thrips and lice) because their mouthparts show the least modification from those of the earliest known fossils. In Hawaii, yellowjackets rob honey bee colonies, killing bees and robbing honey. Distribution of intracellular microbial endosymbioses in insects. These modifications in life cycle and wing development are probably linked to a reduction in the number of larval instars (development of wings in a four-instar ontogeny, with at least the first instar wingless, can hardly be gradual) and with remarkable shortening of development. Photographs of lice from worldwide regions; (a) HL from Japan; (b) HL from China; (c) HL from Nepal; (d) BL from Hungary; (e) HL from USA; (f) BL from USA; (g) BL from Ethiopia; (h) HL from Ethiopia. As a result, endemic prey species are threatened with extinction. From: The Physiology of Insecta (Second Edition), Volume II, 1974, Leticia Avils, Jessica Purcell, in Advances in the Study of Behavior, 2012. These are distinguished by the number of segments in the antennae, tarsi, and labial palps. Stepping-stone colonization may be the major pattern of colonization for rafters. The biological roles of some of these Rickettsia species were reported to include oocyte maturation, parthenogenesis induction, host feminization and the killing of males (Behar et al., 2010; Perotti et al., 2006; Thepparit et al., 2011). Accordingly, they imported about 86 species of parasitic wasps and tachinid flies, mainly to control moth caterpillars. Rapid diversification of sex-determining signals may be due to intragenomic sexual conflict, sex ratio distorters, changing links between environmental conditions and sex-specific fitness, and other evolutionary factors [7]. The most common prey are small insects such as bark lice or planthoppers. However, recent work highlights some major new lineages of insects, and the interplay between habitat, host, and geography is shaping diversification, as has been illustrated by leafhoppers (Bennett and OGrady, 2012), planthoppers (Goodman et al., 2012), cosmet moths (Haines et al., 2014), and bark lice (Bess et al., 2014), as well as Drosophila (Magnacca and Price, 2015). These symbionts are also able to infect the nuclear compartment of a mosquito and a silkworm cell line, indicating its potential to exploit various other insect hosts [45]. On the contrary, thrips and male scale insects have a resting instar(s) but their wing development begins from the third instar similarly as in the typically hemimetabolous Heteroptera. 6. In the Psocoptera, notably the general Clothilla and Lepinotus, sound is also produced by substrate tapping. (F) Red imported fire ant (Solenopsis invicta). (A) Coconut palm rhinoceros beetle (Oryctes nasicornis). They also out-compete them for food resources or displace them by monopolizing nesting or shelter sites. (E) Small hive beetle (Aethina tumida). The Caribbean region is one of the most biogeographically complex island systems and knowledge of the arthropod diversity is still rather poorly known. They often hide away in human goods, and it only requires one fertilized queen to establish a new population. These plants were subsequently sold to consumers along the east coast of the Island, facilitating the spread of Little Fire Ant colonies living in the potting medium. Psocoptera are tiny insects that have either four wings or none at all. Indeed, evolution of new sex determining signals may initiate changes in sex chromosome structure as well as switches from old to new sex chromosomes. 6), but almost certainly earlier. (B) Argentine ant (Linepithema humile). By continuing you agree to the use of cookies. Fig. A.E. We use cookies to help provide and enhance our service and tailor content and ads. (J) Yellow crazy ant (Anoplolepis gracilipes). Invasive insects of Hawaii. They can sometimes cause damage to stored museum collections of insects and plants. In addition to deliberate introductions, 66 species of Ichneumonidae and Braconidae have been accidentally introduced. The wings are held roof-like over their bodies. Adult barklice (like this Graphopsocus cruciatus) are often winged.Photograph by Jean-Jacques Milan, used under GFDL. By the early 20th century its predation on native insects was noted by British naturalist R. C. L. Perkins (1913) who said, It may be said that no native Hawaiian Coleoptera insect can resist this predator, and it is practically useless to attempt to collect [beetles] where it is well established. (1) The microorganisms are restricted to specific insect cells, the sole function of which appears to be to house and maintain the microorganisms; these cells are known as bacteriocytes or mycetocytes (the terms are synonymous), forming organs known as bacteriomes or mycetomes. The microorganisms (collectively displayed here as a circle) transform nitrogenous waste products of the animal (ammonia, urea, etc.) Table 2. In the Hymenoptera, Gontarski (1941) described a similar method of larval stridulation in the hornet, and his postulation that the noises may be hunger calls has been interestingly confirmed by Ishay and Landau (1972) for Vespa orientalis, where the larva emit rhythmically coded sounds which they suggest elicit worker feeding reactions and may signify both the age and the degree of need of the larvae. The general evolutionary trend within Paraneoptera is reduction of the number of instars and compression of wing development to later instars. The total population size can exceed 200 million ants per hectare, or 20,000 ants per square meter, of which 40 will be queens. Most booklice species feed on stored grain, book bindings, wallpaper paste and other starchy products, and on the minute traces of mould found in old books. An exception is Mdmd, which arose through the duplication and subsequent neofunctionalization of CWC22 (nucampholin), a spliceosomal factor gene [16]. As Oboyski et al. Indoor living Psocoptera have poor eyesight, and some of them seem to communicate using sound. The anatomical location and structural organization of the bacteriome vary widely; the bacteriome may be associated with the animal gut (e.g., tsetse flies), fat body (e.g., cockroach), Malpighian tubules (e.g., book lice), or lie free in the body cavity (e.g., aphids). For other Hawaiian lineages, affinities with the north support the idea that insects feeding within seeds can show a pattern of colonization matching their plant hosts. Molecular data indicates a slowing of the diversification over time, perhaps due to slower speciation or higher extinction rates. Examples include Rickettsia species that were detected in flies (tsetse flies, Culicoides sonorensis, Limonia chore), non-hematophagous common booklice (Liposcelis bostrychophila), wasps (Neochrysocharis formosa), true bugs (Acyrthosiphon pisum, Bemisia tabaci, Empoasca papayae), springtails (Onychiurus sinensis), beetles (Adalia bipunctata, Adalia decempunctata, Brachys tessellatus, Coccotrypes dactyliperda, Kytorhinus sharpianus) leeches (Hemiclepsis marginata, Torix tagoi, Torix tukubana), and amoebae (Nuclearia pattersoni) (Mediannikov et al., 2012a; Perlman et al., 2006; Thepparit et al., 2011). Developmental Mechanisms, patterning and evolution, Current Opinion in Genetics & Development, Genotyping, evolution and epidemiological findings of Rickettsia species, Mediannikov et al., 2012a; Perlman et al., 2006; Thepparit et al., 2011, Behar et al., 2010; Perotti et al., 2006; Thepparit et al., 2011, The origin and distribution of human lice in the world, group is likely paraphyletic, it is widely agreed that sucking and chewing lice originated from a common nonparasitic ancestral group closely related to the order, Bacot, 1916; Buxton, 1940; Maunder, 1983; Nuttal, 1919, Intranuclear bacteria: inside the cellular control center of eukaryotes. Evolution: Geology and climate drive diversification. This is because the introduced ants prey on native arthropods. A group of grasshoppers in the Galapagos shows affinities with the Old World, and may be a relict of a previously more widespread distribution or the result of long-distance, trans-Atlantic dispersal (Husemann et al., 2015). Fig. Colonies of these organisms live under dense webbing spun on the bark of trees, branches, and other structures, probably as a predator protection device. The speed and relative freedom with which sex determining signals evolve has been best studied in Diptera, where species are known to have gained and lost heteromorphic sex chromosomes, replaced original sex chromosomes with new ones, incorporated other chromosomal elements into the original sex chromosome, or transitioned from male to female heterogamety [1013]. Although all hymenopterans are haplodiploid, the ploidy signal is mediated by different genes and via different mechanisms. One study described bacteria in ovarian cells of two termite spp. They range in size from microscopic to 1/4-inch. Among vertebrate lineages, the islands have served as the setting for adaptive radiation among those with limited dispersal ability (Losos, 2010). (2004), native Hawaiian insects have suffered increasingly from introduced parasitic wasps in recent decades. They can be found on the ground and in vegetation and will easily fall from trees when disturbed. To our knowledge, no information on such costs or on those of inbreeding depression is available for these organisms. Nitrogen recycling by endosymbiotic microorganisms. Additionally, they have excellent dispersal abilities, high reproductive rates, broad diets and habitat ranges, effective predator defenses, and superior competitive abilities, which enhance their ability to establish, spread, and have a major impact on native ecosystems once they arrive in a new region (Beggs et al., 2011). The yellowjackets are highly predaceous; in Hawaii, their diet includes 14 orders of both invertebrates and vertebrates (Wilson et al., 2009). [46]. The Big-headed ant (Pheidole megacephala) is a native of Africa. The colonies, which may grow to contain many hundreds of individuals, are initiated by a single, apparently inseminated, winged female whose offspring remain together throughout their lives. Where similar or identical sequences are identified in multiple host species of one order or family, the endosymbiont has been assigned a novel candidate generic name (Table 2). Such species tap with the end of their abdomens and produce a faint ticking noise, so they have been called 'ticking spiders'. In the Psocoptera, notably the general Clothilla and Lepinotus, sound is also produced by substrate tapping. A particular focus of debate has been the role of vicariance versus dispersal in shaping the Caribbean biota and the importance of a hypothesized landbridge (GAARlandia) between South America and the Greater Antilles during the Eocene Oligocene transition (Iturralde-Vinent and MacPhee, 1999). Not enough information is available on the biology of these organisms to gain insight into the factors responsible for their inbred systems. External wing occurrence istogether with further shortening of developmentsometimes delayed up to the last preadult instar as in some aphids or even up to the adult stage as in whiteflies. http://www.fossilmuseum.net/Fossil_Galleries/Insect_Galleries_by_Order/Psocoptera/psocopteran_fossil_gallery.htm, http://www.brc.ac.uk/schemes/barkfly/recording.aspx, http://pick5.pick.uga.edu/mp/20q?search=Psocoptera, National Barkfly (Outdoor Psocoptera) Recording Scheme, Copyright1997-2022AmateurEntomologists'Society. Haplodiploid honeybees use zygosity at the sex-determining locus, booklice paternal genome elimination, and butterflies ZW chromosome systems with females as the heterogametic sex [8,9]. LFA are tiny: only 1.6mm long, but their sting is potent. Just on the limits of its range, one may occasionally meet with a few native beetles, often with these ants attached to their legs and bodies, but sooner or later they are quite exterminated from these localities., R.G. For the Hawaiian Islands, taxa known for aerial dispersal abilities (birds and spiders in particular) have generally colonized from the east, in agreement with the direction of extreme storms. In other groups, including Centruroides scorpions (Esposito, 2011) and swallowtail butterflies (Lewis et al., 2015), biogeographic analysis could not reject the hypothesis of dispersal being the only route for colonization of the Caribbean. they have eggs, nymphs and adults) and the order is divided into three suborders - Trogiomorpha, Troctomorpha, and Psocomorpha. Colonization of the Caribbean has been examined for several groups, with spiders in the genera Loxosceles (Sicariidae) (Binford et al., 2008) and Selenops (Selenopidae) (Crews and Gillespie, 2010), as well as butterflies (MatosMarav et al., 2014), supporting the GAARlandia hypothesis in the colonization by the lineages of North from South America. (I) Tropical fire ant (Solenopsis geminata). Graph showing the pace of establishment of introduced ant species in Hawaii from 1878 to 2020. Rickettsiae have also been found in the nuclei of Malpighian tubuli or gut epithelial cells of the booklouse Liposcelis bostrychophila, the moss bug Xenophyes cascus, and the leafhopper Nephotettix cincticeps [4345]. The scientific name comes from the Greek psocus (to grind) and pteron (wing) and refers to the psocopteran jaws, which are shaped to grind food, rather like a pestle and mortar. They are most commonly found in human dwellings and warehouses. Unlike most intranuclear bacteria, they were surrounded by a vacuolar membrane. The extent to which the rate of their diversification varies across taxa, and the reasons behind this variation, remain key questions for future work. Under such conditions, extreme allometry of wing growth certainly favored the evolution of resting nonfeeding instars in the mostly sedentary plant-sucking insects whose life style was a suitable preadaptation. 7. They are generally unculturable and molecular methods have revealed their diversity, including -, -, and -proteobacteria, flavobacteria, and fungi, some of which are not closely related to any formally described taxa. The delayed wing development may (as in whiteflies) or may not (as in aphids) be coupled with the origin of resting stages. Many Rickettsia species have been isolated in arthropods other than the well-known vectors cited above and even in hosts that have no relationships with vertebrates. New (1973) also observed that colonies may fragment and that neighboring colonies may also coalesce. Click for a hub of Extension resources related to the current COVID-19 situation. Intranuclear bacteria enclosed in vacuoles inside the host nucleus were also found in the planthopper Pentastiridius leporinus [47]. Booklice are found around old books, papers and in damp, dark rooms. Blondheim and Shulov (1972) recorded the sounds produced by two species of the Oedipodine grasshopper Acrotylus by drumming its tibiofemoral joint on the ground. In most cases the origin of M-factors is unknown. Primary sex-determining signals have evolved many times independently and act via different mechanisms. 1) (Veracx et al., 2012a,b). Mockford (1957) notes that if females mate before leaving the parental colony, then nearly all matings in Archipsocus must result in close inbreeding. Consistent with this suggestion, sex ratios are highly female biased (Mockford, 1957). Booklice are wingless and are much smaller than barklice (less than 2 mm). Phthiraptera (parasitic lice) may have evolved directly from commensal barklice, and a close relationship between barklice and parasitic lice is also supported by similarities in the structure of their mouthparts. Thus, various arthropod lineages in the Caribbean provided a rich system for testing theories in cladistic biogeography (Liebherr, 1988). wom is a recently evolved chimeric gene, not found even in all species of the same family (Pteromalidae), suggesting that the proximate mechanisms of haplodiploid sex determination may be as varied as in the case of XY heterogametic systems. These insects can be conveniently, if somewhat arbitrarily, discussed in two groups, barklice and booklice, based on whether they tend to live outdoors or in human habitations. Entomologists have discovered that at least 45 non-native ant species are established on the islands, including five of the six of the world's most damaging invasive ants. Ants are not considered native to Hawaii, and many species have been accidentally introduced. A few, such as Liposcelis decolor, can be a pest in grain stores. Sometimes the colonies seem to move in coordinated fashion, rather like sheep. Most research on microorganisms that provide specific classes of primary nutrients, such as amino acids and vitamins, has focused on intracellular endosymbionts of insects that are restricted to specific organs, variously known as mycetomes or bacteriomes (Table 2). The identity and function of the microorganisms have received little study, but a nutritional role is often invoked. (2018). Dumortier (1966) described a new method of stridulation in Orthoptera from the Pamphagid Eunopius terulentus, in the female of which sound is produced by tapping the elytra against the knees of the mesothoracic legs. Gillespie, in Encyclopedia of Evolutionary Biology, 2016. In return for meals of sweet honeydew secretions from these insects, the ants protect them from predation. Where closely related species share a homologous M-factor, its sequence can diverge rapidly (e.g. Roth and Hartman (1967) describe how the blattids Leucophaea maderae and Eublaberus posticus tap the substrate, which may include the female, with the end of the abdomen, producing rhythmic sounds, apparently of significance in courtship. 1. These M-factors are all unrelated to each other, reflecting their independent evolution [16,17,1820]. Social Hymenoptera in particular seem well adapted to dispersal by accidental human transport. Haskell, in The Physiology of Insecta (Second Edition), Volume II, 1974. Nature 509, 297298. Although studies to date have provided insights into how individual lineages have colonized and subsequently diversified within the island system, there are as yet no unifying principles to explain the origin and diversification of Caribbean taxa. Though more work is needed, it is clear that genetic mixing and hybridization among recently diverged populations play a key role in fostering adaptive radiation, as has been suggested for spider lineages (Roderick et al., 2012).