Testing concordance in species boundaries using acoustic,morphological, and molecular data in the field cricket genus Itaropsis (Orthoptera: Grylloidea,Gryllidae: Gryllinae)

In most taxa, species boundaries are inferred based on differences in morphology or DNA sequences revealed by taxonomic or phylogenetic analyses. In crickets, acoustic mating signals or calling songs have species‐specific structures and provide a third data set to infer species boundaries. We examined the concordance in species boundaries obtained using acoustic, morphological, and molecular data sets in the field cricket genus Itaropsis. This genus is currently described by only one valid species, Itaropsis tenella, with a broad distribution in western peninsular India and Sri Lanka. Calling songs of males sampled from four sites in peninsular India exhibited significant differences in a number of call features, suggesting the existence of multiple species. Cluster analysis of the acoustic data, molecular phylogenetic analyses, and phylogenetic analyses combining all data sets suggested the existence of three clades. Whatever the differences in calling signals, no full congruence was obtained between all the data sets, even though the resultant lineages were largely concordant with the acoustic clusters. The genus Itaropsis could thus be represented by three morphologically cryptic incipient species in peninsular India; their distributions are congruent with usual patterns of endemism in the Western Ghats, India. Song evolution is analysed through the divergence in syllable period, syllable and call duration, and dominant frequency. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 285–303.     

Song mimicry of Black-bellied Firefinch Lagonosticta rara and other finches by the brood-parasitic Cameroon Indigobird Vidua camerunensis in West Africa

Brood-parasitic finches Vidua spp. mimic songs of their foster species, with most Vidua species both mimicking songs and parasitizing nests of a single estrildid finch species. We describe a behavioural radiation in the Cameroon Indigobird Vidua camerunensis . Local populations are polymorphic in behaviour, each male mimicking songs of a single species, with certain males mimicking songs of one species and other males mimicking songs of another host species. The species most often mimicked in song are Black-bellied Firefinch Lagonosticta rara and African Firefinch L. rubricata ; other species mimicked in song are Brown Twinspot Clytospiza monteiri and Dybowski's Twinspot Euschistospiza dybowskii . Indigobirds in the different mimicry song populations do not differ morphologically in plumage colour or size. The lack of morphological differences between male indigobirds with different mimicry songs is consistent with a recent behavioural radiation through host shifts, perhaps facilitated by environmental change associated with prehistoric cultivation of grain. The mimicry song populations of indigobirds, behaviourally imprinted upon different host species, support the idea of a process of speciation driven by a shift to new host species.     

NECROSIS OF LUNG EPITHELIAL CELLS BY FILARIAL PARASITIC PROTEIN VIA AN EARLY INDUCTION OF c-H-rasAND TNFα EXPRESSION

The direct interaction of filarial proteins with lung epithelial cells was examined to determine the possible mechanism of inducing cell death, an event that is observed in patients with tropical pulmonary eosinophilia. Exposure of lung epithelial cells to filarial parasitic proteins,Brugia malayi(BmA),Setaria digitata(Sd), and recombinant filarial protein (pGT 7)in vitrofor more than 2 days, causes the appearance of DNA fragments both in the cytoplasm and culture supernatants, while no fragmentation was observed in the untreated controls. The release of DNA fragments both in the cytoplasm and the culture supernatants simultaneously, indicates that cell death is induced by a necrotic event rather than apoptosis. Fluorescent-labelled studies also indicate the fragmentation of DNA increasing in a time-dependent manner. Normal cellular function is controlled through several oncogenes. The modulation of specific proto-oncogenes like myc, ras and TNFα during exposure to filarial parasitic proteins reveal elevated levels of expression of ras and TNFα as early as 2 hours, implicating their involvement prior to DNA fragmentation leading to pathogenesis.     

A Comparative Study of Bivalves Which Bore Mainly by Mechanical Means

This account of the boring mechanisms of those bivalve groupswhich bore mainly by mechanical means attempts to show partlyby reference to published accounts of boring and partly fromour own recent observations of certain characteristics of theboring process in the Pholadidae and Petricolidae, that in contrastto the movements of burrowing forms from which originally allthe boring movements derive, the process of boring makes fewdemands on the hydrodynamic system of the bivalve. The characteristicsof the boring process are closely related to the movements inmodern forms having epifaunal or infaunal habits, supportingthe suggestions of Yonge (1963) concerning the origin of thishabit in the Bivalvia. In all groups in which boringis mechanical,the shell forms the boring tool. However, in those groups inwhich boring has its origin in the epifaunal habit, the majorforce applied to the shell in abrading the burrow isprovidedby contractions of the pedal or byssal retractor muscles. Inthe Adesmacea alone, where boring has been derived from a deepburrowing habit, the adductor muscles provide the major forcein abrasion, and the basic digging cycle has become specializedby the addition of the rocking action of the valves which succeedsretraction. In the former group the ligament is retained andprovides the strong outward force with which the shell is heldagainst the wall of the burrow. In the latter group, the ligamentis reduced, allowing the valves to rock, but here the reciprocalaction of the adductors allows the valves to diverge anteriorlyas the large posterior retractor muscle contracts. In the morespecialized species, water pressure plays a minor role, themaximum pressures recorded being associated with actions subordinateto those involved primarily in abrasion, such as rotation inthe burrow or expulsion of debris from the burrow aspseudofeces.The least specialized borers, such as Petricola, resemble burrowingforms in the importance of the hydrodynamic role of the bodyfluids. In all groups there is a tendency for hypertrophy totake place in the muscles which produce the main boring effect,and for their action to be applied with maximum mechanical advantageagainst a fulcrum provided in most cases by the foot.     

Density‐dependent polyphenism and baculovirus resistance in teak defoliator,Hyblaea puera (Cramer)

1. Field populations of the teak defoliator larvae, Hyblaea puera Cramer exhibit colour polyphenism under different population densities: greyish‐green with black‐ and orange‐coloured dorsal bands in low‐density endemic populations and uniformly black or intermediate colour during high‐density population. 2. The density dependence of colour polyphenism was confirmed by field monitoring of H. puera populations during 2008–2010. 3. The above findings were later substantiated by rearing H. puera larvae under different densities (i.e. solitary and crowded in the laboratory). Ninety one per cent of the solitary reared laboratory population developed bright coloration whereas, 92% of the group reared larvae turned to black. Eight per cent of larvae from both the rearing densities were of intermediate colour. 4. Density‐dependent resistance build‐up against H. puera nucleopolyhedrovirus by H. puera were tested using the fifth instar larvae. The results showed three‐fold increase of median lethal dose (LD₅₀) value for the group reared larvae (5332 polyhedral occlusion bodies/larvae) compared to the solitary reared ones (1727 polyhedral occlusion bodies/larva) and also significant difference for the mean time to death (3.6 and 3.3 days, respectively). 5. The study revealed the strong influence of larval density on H. puera larval melanism and resistance build‐up against H. puera nucleopolyhedrovirus.     

Large herbivores in Upper Lupande Game Management Area, Luangwa Valley, Zambia

Upper Lupande Game Management area in Luangwa Valley, Zambia currently supports good populations of sixteen large and medium-sized herbivores. Impala was the most abundant constituting 34% of the total population estimates, followed by buffalo (19%), zebra (12%), wildebeest (10%), warthog (8%), elephant (6%) and hippopotamus (3%). Other species made up the remaining 8%. The survey zone contained a herbivore biomass of 10,796.18 times 10³ kg. Elephants contributed 50.2% and buffalo 25.1% of the total herbivore biomass of the area. The estimated maximum sustainable off-take potential in Upper Lupande was 1110.14 times 10³kg per annum. The distribution of most of the species studied suggested favourable recruitment status. There were species-specific distribution patterns and densities in the survey zone.