Hasan Sevgili
Ordu University
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Publication
Featured researches published by Hasan Sevgili.
The Journal of Experimental Biology | 2014
Ian C. Kutch; Hasan Sevgili; Tyler Wittman; Kenneth M. Fedorka
As temperatures change, insects alter the amount of melanin in their cuticle to improve thermoregulation. However, melanin is also central to insect immunity, suggesting that thermoregulatory strategy may indirectly impact immune defense by altering the abundance of melanin pathway components (a hypothesis we refer to as thermoregulatory-dependent immune investment). This may be the case in the cricket Allonemobius socius, where warm environments (both seasonal and geographical) produced crickets with lighter cuticles and increased pathogen susceptibility. Unfortunately, the potential for thermoregulatory strategy to influence insect immunity has not been widely explored. Here we address the relationships between temperature, thermoregulatory strategy and immunity in the fruit fly Drosophila melanogaster. To this end, flies from two separate Canadian populations were reared in either a summer- or autumn-like environment. Shortly after adult eclosion, flies were moved to a common environment where their cuticle color and susceptibility to a bacterial pathogen (Pseudomonas aeruginosa) were measured. As with A. socius, individuals from summer-like environments exhibited lighter cuticles and increased pathogen susceptibility, suggesting that the thermoregulatory–immunity relationship is evolutionarily conserved across the hemimetabolous and holometabolous clades. If global temperatures continue to rise as expected, then thermoregulation might play an important role in host infection and mortality rates in systems that provide critical ecosystem services (e.g. pollination), or influence the prevalence of insect-vectored disease (e.g. malaria).
Journal of Orthoptera Research | 2004
Klaus-Gerhard Heller; Fer Willemse; Hasan Sevgili
Abstract Description of a new subspecies of Poecilimon mytilenensis Werner 1932. Both the new and the nominate subspecies occur on the island of Lesbos, Greece. Both subspecies differ mainly in the length of the tip of male subgenital plate. In addition to morphological data and a detailed distribution map, descriptions and oscillograms of male song of both subspecies, female song of the nominate subspecies and some data on the unusual mating behavior (ampulla mass 15 % of male body mass) are provided.
Italian Journal of Zoology | 2000
Hasan Sevgili; Battal Çiplak
Abstract Previous records and 1920 newly collected specimens formed the basis of this survey of the Orthoptera of Şanliurfa (Urfa) province in southeastern Turkey. Eighty‐six species and subspecies were recorded, both as the result of the field study and use of published data; they belong to seven families and fifty genera. Eleven genera and thirty‐two species were recorded for the first time from Şanliurfa. Seven species were recorded as new for the southeastern Anatolia. Eleven species with subspecies are endemic to Anatolia. Eremial faunal elements are dominant in the area.
Behaviour | 2007
Hasan Sevgili; Klaus Reinhold
Theoretical models predict that males should allocate sperm in response to female quality and empirical studies have shown that fecundity traits including age, mass and mating status can influence male sperm allocation strategies. We tested whether female size has an influence on sperm allocation in the bushcricket Poecilimon jonicus jonicus (Orthoptera: Phaneropterinae). Contrary to other studies, we found neither evidence of strategic sperm allocation in response to female size nor an effect of female size on spermatophore size. Male age and mating history was positively related to sperm number during sequential matings, but had no effect on spermatophylax or ampulla weight. Spermatophore weight, but not sperm number, was positively correlated with male body weight. Ampulla weight was positively correlated with spermatophylax weight.
Journal of Orthoptera Research | 2002
Ali Demirsoy; Selahattin Salman; Hasan Sevgili
Abstract A new genus, Novadrymadusa, and a new species, N. karabagi, are described. A new combination, N. kurda (Uvarov), is established. Together with a key to species in the new genus there is a short account of its geographical distribution and that of related genera.
Journal of Orthoptera Research | 2001
Hasan Sevgili
Abstract New data on the distribution and systematics of Turkish species of Poecilimon Fischer, 1853, are presented. A new species (Poecilimon demirsoyi sp. n.) and the insufficiently known females of Poecilimon birandi Karabag and Poecilimon haydari Ramme are described, and some new distributional records given.
Insect Systematics & Evolution | 2008
Klaus-Gerhard Heller; Hasan Sevgili; Klaus Reinhold
In this paper a combination of characters is described by which Poecilimon species (Orthoptera, Tettigonioidea, Phaneropteridae) can be recognised as members of the P. syriacus group. All species occur in or around Anatolia – from the island of Samos in the West and the provinces of Artvin and Bitlis in the East to Jerusalem in the South. The molecular data (Ullrich 2007) suggest the following not completely resolved relationship (ersisi (syriacus, (karakushi, (angulatus, obtusicercus n. sp.)), (xenocercus, karabukensis), ((izmirensis, ege) serratus))), while P. uvarovi and P. adentatus as well as P. kutahiensis (molecular data missing) are also considered to belong to the group according to song and/or morphology. The morphological data previously used to define the group are not sufficient to recognize all of its members. Some species differed distinctly in the structure of male genitalia, but the calling songs of all species studied are characterized by an unusually high syllable repetition rate and low number of impulses per syllable. Thus the evolution of genitalia seems to be faster than that of song patterns.
Journal of Insect Behavior | 2015
Hasan Sevgili; Hülya Önal; Arzu Yiğit
Bushcrickets comprise an important group of model organisms, which are intensively studied to understand the evolution of mating behavior. During the mating process, the male bushcricket transfers a costly and edible spermatophore consisting of two parts to the female. This unique behavior makes bushcricket species appropriate study organisms for investigating spermatophore size variations across entire bushcricket family (Tettigoniidae). The functions of the spermatophylax and the ampulla, which constitute the spermatophore, have been addressed in many studies. Although the costs and benefits of mating for male and female bushcrickets may vary depending on species, there are some common evolutionary traits. In the present study, mating behaviors and spermatophore characteristics of two endemic bushcricket species, Phonochorion uvarovi and P. artvinensis, distributed at the high altitudes of the Kaçkar Mountains, northeastern Turkey, were examined. The data on two closely related species belonging to the genus of Phonochorion show that they have different reproductive investments in terms of spermatophore and sperm numbers in spite of similar habitat and nutritional preferences. P. artvinensis had a larger spermatophore, spermatophylax and ampulla, but transferred fewer sperm. Male age and weight had a significant effect on spermatophore, spermatophylax and ampulla investments in P. uvarovi while only male weight was a significant factor in P. artvinensis. A positive relationship between the spermatophylax and the ampulla weights in both species supports the ejaculate protection hypothesis in the Phonochorion species. Even though further studies on Phonochorion should be conducted to provide a more clear comparison with other groups in the barbitistine, this study demonstrates that both P. uvarovi and P. artvinensis make little spermatophore investment relative to their body size in comparison to other barbitistines.
Zoology in The Middle East | 2014
Hasan Sevgili; Muhammed Ali Özata
A checklist of the species of springtails (Hexapoda: Collembola) hitherto recorded from Turkey is presented. This list contains 53 species belonging to 39 genera in 13 families. The diversity of Collembola in Turkey is poorly known and it is clear that numerous species wait to be discovered.
Zootaxa | 2018
Hasan Sevgili; Deniz Şirin; Klaus-Gerhard Heller; Michèle Lemonnier-Darcemont
The aim of this study is to conduct a detailed taxonomic revision of the Poecilimon (Poecilimon) zonatus species-group (Orthoptera: Phaneropterinae) using both morphology and bioacoustics. Two new species (Poecilimon (Poecilimon) salmani, P. (P) azizsancar) and one new subspecies (P. (P) zonatus datca) are described. Based on the data, we conclude that the species complex can be separated into two subgroups (P. tauricola and P. zonatus). Within the P. zonatus subgroup, song structures indicate P. variicercis as basal branch since producing two syllable types is possibly a derived character. From both, from bioacoustics and morphology, it is concluded that the relationships between species of the group are as follows: P. tauricola subgroup (P. tauricola + P. azizsancar) + P. zonatus subgroup (P. variicercis + (P. varicornis + (P. zonatus zonatus+P. zonatus datca)) + (P. salmani+P. vodnensis)))). Except for two species (P. vodnensis and P. varicornis), the other species of the group are all distributed in Anatolia. P. vodnensis is known only from Macedonia, whereas, P. varicornis has been recorded only from Syria and Lebanon. We assume that the group originated from an Anatolian ancestral stock and expanded its distribution to the Balkans through Taurus Way and Dardanelles. Other ancestral populations may have also spread in the north-south directions through the appropriate steppe corridors in the Anatolian Diagonal Mountains and in its vicinity.