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We studied circular sand pile formation by two colonies of Brazilian Dorymyrmex ants, in which workers dumped sand excavated from their underground nest around the nest entrance hole. In most cases a worker dumped its load just beyond the ridge of the pile. Each dumped piece either stayed where it was deposited (81.9% in colony A and 73.0% in colony B) or rolled down the outer slope of the sand pile away from the entrance (17.9% in colony A and 27.0% in colony B). Ants almost never dumped in a way that resulted in the load rolling back to the entrance. When one side of the sand pile was experimentally removed, ants preferentially dumped soil on the now flat side, thereby restoring the original circular shape. 相似文献
3.
Sarie Van Belle Alejandro Estrada Karen B. Strier 《International journal of primatology》2008,29(6):1481-1498
We investigated male social relationships in 2 groups of black howlers (Alouatta pigra) in Palenque National Park, Mexico, over a 14-mo study characterized by frequent changes in male group membership. Both single
males and pairs of males entered our focal groups. Single males tended to join groups, whereas pairs of males entering groups
together successfully evicted resident males. The 19 male dyads across the 11 periods defined by changes in group membership
were rarely in close proximity or interacting with one another. Nevertheless, 1 male formed significantly closer associations
with resident females in 6 periods and achieved higher mating success during 4 of the periods when ≥1 female was sexually
active. In the other 5 periods, no particular male maintained significantly closer associations with resident females, which
may be a result of the rapid sequence of changes in male membership and corresponding social instability. Resident males participated
frequently and consistently in mutual howling, but the resident male with the strongest female associations and highest mating
success initiated howling bouts more frequently in all but 1 of the 6 socially stable periods. Though still preliminary, our
findings suggest that variation in social relationships among male black howlers may be more related to their ability to establish
strong relationships with females than to their relationships with one another. 相似文献
4.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae. 相似文献
5.
Hirokazu Yamada Masatoshi Tomaru Muneo Matsuda Yuzuru Oguma 《Journal of Insect Behavior》2008,21(4):222-239
Drosophila ananassae and D. pallidosa are closely related, sympatric species that lack postmating isolation. Sexual isolation has been considered important in
maintaining them as independent species. To clarify the behavioral processes leading to sexual isolation, we analyzed behavioral
sequences and examined the effect of courtship song on mating success and on behaviors of both sexes by surgically removing
male wings (song generators), female aristae (song receivers), or female wings (means of fluttering). We found that heterospecific
courtship songs evoked female wing fluttering, whereas conspecific courtship song did not. Furthermore, female wing fluttering
made courting males discontinue courtship. These findings suggest that strong sexual isolation is achieved through the following
behavioral sequence: heterospecific song→female wing fluttering→courtship discontinuation. 相似文献
6.
Agonistic behaviour and the significance of acoustic threat displays were investigated in juvenile red-finned loaches, Yasuhikotakia modesta. This species produced two different vocalizations during agonistic encounters—clicks and butting sounds. Clicks were produced
at some distance from the opponent whereas butting sounds were emitted when one fish touched the other with its mouth. This
occurred primarily during circling. Both sound types were short broadband signals with the main energies concentrated at about
230 Hz, but clicks were longer in duration and lower in sound level. Agonistic behaviour usually started when one fish approached
the other, spread its fins and produced clicks (threat displays), which was followed by parallel displaying, circling and
chasing. All fish approached a mirror quickly and displayed aggressively in a parallel position. The number and duration of
the threat displays in front of the mirror image were significantly elevated compared with control experiments (rear of the
mirror). When playing back click trains in the presence of a mirror image, loaches vocalized significantly less often than
during the silent periods, whereas the amount of lateral displaying remained similar. These data indicate that agonistic sounds
reduced acoustic displays in red-finned loaches. 相似文献
7.
Chinnadurai Sreenath Kumar Dronamraju V. L. Sarada Thomas Paul Gideon Ramasamy Rengasamy 《World journal of microbiology & biotechnology》2008,24(9):1989-1992
The antibacterial properties of the three seagrasses namely Cymodocea serrulata, Halophila ovalis and Zostera capensis were tested against the human pathogens Staphylococcus aureus, Bacillus cereus, B. subtilis, Escherichia coli, Salmonella paratyphi, Salmonella typhimurium and Micrococcus luteus, using six different solvents namely, petroleum ether, chloroform, ethyl acetate, acetone, methanol and water. Ethyl acetate
and methanol extracts showed maximum activity against most of the pathogens when compared to other solvents. Experiments are
underway to isolate active compound(s) implicated in controlling the growth of the pathogens in vitro. 相似文献
8.
This study was undertaken to study the antifungal activity of Pleurotus cystidiosus against Colletotrichum gloeosporioides. This was achieved by fractionating the mushroom, P. cystidiosus initially to acetone (A), dichloromethane (D), and hexane (H) and studying the antifungal activity using the standard poisoned food technique. All the test solutions used were in the concentration of 20,000 ppm. The percentage inhibition of extracts A, D, and H was 12, 7, and 0.4%, respectively. Antifungal assay guided fractionation of the most active extract A resulted in four fractions; A1, A2, A3, and A4 having 12, 22, 0, and 17% percentage inhibitions, respectively. Fractions A2 and A4 were selected for further purifications. Normal phase column chromatography of A2 gave A2-1, A2-2, A2-3, and A2-4, with percentage inhibitions 7, 5, 26, and 13%, respectively. The fraction with the highest inhibitory activity (A2-3) was further separated using the Chromatotron and a single compound (A2-3-13) with 41% inhibition was isolated. Structure elucidation of this compound using 1D and 2D NMR spectroscopy proved this compound to be 3beta, 5alpha, 6beta-trihydroxyergosta-7,22-diene. 相似文献
9.
Rory J. Mc Donnell Timothy D. Paine Michael J. Gormally 《Journal of Insect Behavior》2007,20(3):367-376
The ability of neonate larvae of the aquatic sciomyzids, Sepedon spinipes spinipes (Scopoli) and Dictya montana Steyskal (Diptera), to follow snail mucus trails was assessed using filter paper Y-mazes. On finding a mucus trail, larval
behaviour of both species switched from unstimulated to stimulated searching behaviour, the latter being characterised by
an increase in larval velocity and the frequency of lateral head taps. When fresh mucus trails were used, all of the neonates
displayed a positive response and followed the mucus trail into the experimental arm. In addition, for S. s. spinipes and D. montana 80.00% and 86.67% of larvae respectively exhibited a strong response and followed the trail to its end. The stimulatory substance
(s), however, appears to become inactive with time and after 45 minutes none of the tested larvae reached the trail end. These
results are discussed in relation to the ability of aquatic species to forage outside of water for prey and the implications
for their use in the biological control of nuisance snails. 相似文献
10.
M. E. Cocom Pech W. de J. May-Itzá L. A. Medina Medina J. J. G. Quezada-Euán 《Insectes Sociaux》2008,55(4):428-433
Euglossa viridissima is an orchid bee that forms both solitary and multiple female nests, making it a suitable species for the study of factors
leading to diverse degrees of sociality in Euglossines. We conducted observations in eight reused nests (where a first generation
of bees had been produced) kept in artificial boxes from the Yucatan Peninsula, Mexico. Five nests were reused (reactivated)
by a single female (SFN), two nests reused by a mother and one daughter (MFN1) and one nest reused by the mother and two daughters
(MFN2). No single nest was reactivated by unrelated females. The number of foraging trips, their duration and the duration
of cell provisioning was not different between SFN and MFN. The overall production of cells per female was not different either
between both types of nest. However, in MFN although all females did lay eggs, there was a reproductive skew in favor of the
mother (95 and 45% of the brood produced in MFN1 and MFN2 respectively). She showed reproductive control of her daughters
through oophagy and displaying threatening behavior when the daughters tried to open a cell where she had laid an egg. Brood
losses to parasites (Anthrax sp. (Bom-byliidae) and Hoplostelis bivittata (Megachilidae)) were only found in SFN which possibly reflects and advantage of MFN in this respect. Our results coupled
with other studies in Euglossa, reveal that a wide range of social behaviors occur in this genus, from solitary and communal to primitive reproductive division
of labor. Multiple factors involving different levels of pressure imposed by food availability and parasites may favor such
a diverse range of nesting behaviors. Interestingly, female associations in E. viridissima seem a result of kin selection that is enforced by coercion from mother females on their daughters. More studies are needed
to shed light upon the social organization of Euglossa and other Euglossines and on their phylogenetic relationships in order to trace the origins of eusociality in Apidae.
Received 12 February 2008; revised 25 June 2008; accepted 17 July 2008. 相似文献
11.
A Comparison of Female Mating Strategies in <Emphasis Type="Italic">Pan troglodytes</Emphasis> and <Emphasis Type="Italic">Pongo</Emphasis> spp. 总被引:1,自引:1,他引:1
Orangutans and chimpanzees differ in many aspects of their mating and social systems. Nevertheless, because both great apes
require enormous maternal investment in offspring and because female reproductive potential is limited, female orangutans
and chimpanzees should be selective of their mates, yet expected to exhibit anti-infanticide strategies such as mating with
multiple males. We review and compare mating patterns in orangutans and chimpanzees to understand how these critical pressures
are filtered through the different demands of the socioecology of each species. We highlight the variation in female mating
behavior as a function of the proximity of ovulation. We conclude that both genera pursue tactics for paternity confusion
by mating with multiple males and by mating cooperatively or even proceptively with nonpreferred partners when conception
is unlikely. Mating selectivity is suggested by variation in proceptive behavior toward particular partners and by increased
resistance of nonpreferred partners during the periovulatory period. Thus, data for both species support a mixed mating strategy
whereby females shift their mating behavior in accordance with ovulatory status to accommodate the competing demands of mate
selectivity and paternity confusion. 相似文献
12.
Kurtzman CP 《Antonie van Leeuwenhoek》2011,100(3):455-462
Ogataea
parapolymorpha sp. n. (NRRL YB-1982, CBS 12304, type strain), the ascosporic state of Candida
parapolymorpha, is described. The species appears homothallic, assimilates methanol as is typical of most Ogataea species and forms hat-shaped ascospores in asci that become deliquescent. O. parapolymorpha is closely related to Ogataea
angusta and Ogataea
polymorpha. The three species can be resolved from gene sequence analyses but are unresolved from fermentation and growth reactions
that are typically used for yeast identification. On the basis of multiple isolates, O. angusta is known only from California, USA, in association with Drosophila and Aulacigaster flies, O. parapolymorpha is predominantly associated with insect frass from trees in the eastern USA but O. polymorpha has been isolated from various substrates in the USA, Brazil, Spain and Costa Rica. 相似文献
13.
Noel H. Holmgren 《Brittonia》2018,70(1):115-139
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations. 相似文献
14.
Recently, the prenyltransferase SirD was found to be responsible for the O-prenylation of tyrosine in the biosynthesis of sirodesmin PL in Leptosphaeria maculans. In this study, the behavior of SirD towards phenylalanine/tyrosine and tryptophan derivatives was investigated. Product
formation has been observed with 12 of 19 phenylalanine/tyrosine derivatives. It was shown that the alanine structure attached
to the benzene ring and an electron donor, e.g., OH or NH2, at its para-position are essential for the enzyme activity. Modifications were possible both at the side chain and the benzene ring.
Enzyme products from seven phenylalanine/tyrosine derivatives were isolated and characterized by MS and NMR analyses including
HSQC and HMBC and proven to be O- or N-prenylated derivatives at position C4 of the benzene rings. K
M
values of six selected derivatives were found in the range of 0.10–0.68 mM. Catalytic efficiencies (K
cat/K
M
) were determined in the range of 430–1,110 s−1·M−1 with l-tyrosine as the best substrate. In addition, 7 of 14 tested tryptophan analogs were also accepted by SirD and converted to
C7-prenylated derivatives, which was confirmed by comparison with products obtained from enzyme assays using a 7-dimethylallyltryptophan
synthase 7-DMATS from Aspergillus fumigatus. 相似文献
15.
Male spider monkeys direct the majority of their aggression toward adult females, and the aggressive interactions may be a
form of sexual coercion. We investigated female-directed male aggression in 2 wild communities of spider monkeys (Ateles geoffroyi yucatanensis) from the Otoch Ma’ax Yetel Kooh Reserve in Yucatan, Mexico to evaluate the sexual coercion hypothesis. The aggression occurred
in 2 distinct forms: physical aggression and prolonged noncontact chases. The latter appeared highly ritualized in nature
and accounted for >80% of all female-directed male aggression. Rates of prolonged chases, but not physical aggression, peaked
when the female target was likely cycling and were associated with male place-sniffing of the substrate previously occupied
by the female target. Prolonged chases were also associated with proceptive behavior directed from the female target toward
her male attacker after the chase had ceased. Our data therefore suggest that prolonged chases are sexually motivated. Prolonged
chases did not result in immediate copulation, but sometimes the female victim left the subgroup to travel alone with her
male aggressor, and thus prolonged chases may be a form of male intimidation to coerce females into a mating consortship.
However, as prolonged chases appeared highly ritualized, the chases may also be a form of male sexual display. Further investigation
of the costs incurred by female recipients of prolonged chases is therefore required before one can interpret the behavior
as sexual coercion. 相似文献
16.
Serena Santolamazza-Carbone Montserrat Pestaña Nieto Rosa Pérez Otero Pedro Mansilla Vázquez Adolfo Cordero Rivera 《BioControl》2009,54(2):195-209
We investigated the effects of temperature, photoperiod, food and host availability, and body size on the overwintering abilities
of the egg parasitoid Anaphes nitens Girault (Hymenoptera, Mymaridae) under natural conditions. Seven groups of eighty females received one of four treatments
(n = 20): (i) honey and hosts, (ii) water and hosts, (iii) honey, or (iv) water. Seven groups of forty males received only honey
or water (n = 20). To test if short day-length is the main cue for larval dormancy, the experiment was replicated inside a climate chamber
at 20°C and under a winter photoperiod. A. nitens overwinters because of quiescence or oligopause inside the hosts and increased adult longevity. Mean pre-emergence mortality
was up to 26% indoors and 15.2% outdoors, males being more affected. Development time had a significant and positive effect
on body size. Honey-fed females without hosts had the highest longevity (53 days). Mother’s diet and size affected development
time, body size, longevity, and fecundity of the progeny. The results confirm the good adaptation of the parasitoid to the
environmental conditions of NW Spain and its ability to synchronize its life cycle with the phenology of the host.
Handling editor: Drik Babendreier. 相似文献
17.
Previously it was shown that the Arabidopsis apyrase genes AtAPY1 and AtAPY2 are crucial for male fertility because mutant pollen (apy1-1; apy2-1) with T-DNA insertions in both genes could not germinate (Steinebrunner et al. (2003) Plant Physiol. 131: 1638–1647). In this study, pollen germination was restored and apyrase T-DNA double knockouts (DKO)
apy1-1/apy1-1; apy2-1/apy2-1 were generated by complementation with AtAPY2 under the control of a pollen-specific promoter. The DKO phenotype displayed developmental defects including the lack of
functional root and shoot meristems. In cotyledons, morphogenetic and patterning abnormalities were apparent, e.g., unlobed
pavement cells and stomatal clusters. Another set of lines was created which carried either AtAPY1 or AtAPY2 under a dexamethasone-(DEX)-inducible promoter as an additional transgene to the pollen-specific gene construct. Application
of DEX did not reverse the DKO phenotype to wild-type, but some inducible lines exhibited less severe defects even in the
absence of the inducer, probably due to some background expression. However, even these DKO mutants were seedling-lethal and
shared other defects regarding cell division, cell expansion and stomatal patterning. Taken together, the defects in the DKO
mutants demonstrate that AtAPY1 and AtAPY2 are essential for normal plant development. 相似文献
18.
New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora:
Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii
,
Rumex densiflorus var. pycnanthus
,
R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage. 相似文献
19.
William O. Sabino Cláudia Inês da Silva Isabel Alves-dos-Santos 《Journal of Insect Behavior》2017,30(1):103-118
We describe the mating behaviour of males of Centris (Paracentris) burgdorfi, a solitary, univoltine bee, with a wide distribution in Brazil. We also describe the unusual sleeping sites of males and females. The study was performed during two breeding seasons, in northeastern Brazil, where the species nests in aggregations in petrified dunes. Data on mating behaviour were collected through direct observations of the bees at the nesting-emergence site. Males compete intensely for virgin females in the morning, sometimes killing rivals. The high competition for females near the nesting site makes that the male has to take the female to another place to get genital contact. In the evening, males do not use plants to spend the night, instead they aggregate in sleeping clusters inside old burrows in the nesting-emergence area while females sleep in groups on plants that provide the floral oil used in nest construction. 相似文献
20.
Nehme N Mathieu F Taillandier P 《Journal of industrial microbiology & biotechnology》2008,35(7):685-693
This study examines the interactions that occur between Saccharomyces cerevisiae and Oenococcus oeni strains during the process of winemaking. Various yeast/bacteria pairs were studied by applying a sequential fermentation strategy which simulated the natural winemaking process. First, four yeast strains were tested in the presence of one bacterial strain leading to the inhibition of the bacterial component. The extent of inhibition varied widely from one pair to another and closely depended on the specific yeast strain chosen. Inhibition was correlated to weak bacterial growth rather than a reduction in the bacterial malolactic activity. Three of the four yeast strains were then grown with another bacteria strain. Contrary to the first results, this led to the bacterial stimulation, thus highlighting the importance of the bacteria strain. The biochemical profile of the four yeast fermented media exhibited slight variations in ethanol, SO(2) and fatty acids produced as well as assimilable consumed nitrogen. These parameters were not the only factors responsible for the malolactic fermentation inhibition observed with the first bacteria strain. The stimulation of the second has not been reported before in such conditions and remains unexplained. 相似文献