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Unripe Fruits (unripe + fruit)
Selected AbstractsForaging by fearful frugivores: combined effect of fruit ripening and predation riskFUNCTIONAL ECOLOGY, Issue 6 2006J. M. FEDRIANI Summary 1Plant defensive compounds and predation risk are main determinants of herbivore foraging, though empirical studies have seldom measured the combined effects of these two factors. By considering the interaction between the herb Helleborus foetidus and its main fruit and seed predator, the Wood Mouse Apodemus sylvaticus, we evaluated whether the defensive role against seed predators of compounds present in H. foetidus unripe fruits holds across a micro-landscape that differs in foraging costs (i.e. predation risk). 2First, we used standardized food patches that simulated fruiting H. foetidus plants to ascertain fruit preferences of captive mice. Then, by means of field experiments, we assessed the combined effects of fruit ripening and predation risk on foraging by free-ranging mice. 3Captive mice avoided plants with unripe fruit and avoided consuming unripe fruits within a particular plant. Free-ranging mice also avoided unripe fruits in safe microhabitats (rocky substrate), but not in risky microhabitats (bare ground) where few fruits were consumed. This unexpected result may be driven by predation risk experienced by mice foraging on H. foetidus fruits, and/or plant defensive compounds acting in a dose-dependent manner. 4Frugivorous mice responded to both chemical defences present in unripe H. foetidus fruits as well as to predation cost though such response was sequential. Plant defence compounds appeared to play a part in mouse foraging only after mice selected low predation risk microhabitats. 5Our study indicates that both digestive and ecological factors influence foraging decisions, which in turn affects pressures exerted by herbivores on plant populations. [source] Foraging and ranging behavior during a fallback episode: Hylobates albibarbis and Pongo pygmaeus wurmbii comparedAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2009Erin R. Vogel Abstract Periodic episodes of food scarcity may highlight the adaptive value of certain anatomical traits, particularly those that facilitate the acquisition and digestion of exigent fallback foods. To better understand the selective pressures that favored the distinctive dental and locomotor morphologies of gibbons and orangutans, we examined the foraging and ranging behavior of sympatric Hylobates albibarbis and Pongo pygmaeus wurmbii during an episode of low fruit availability at Tuanan, Kalimantan Tengah, Indonesia. We found that Hylobates ranged 0.5 km day,1 or 33% farther than did Pongo, but the overall daily ranging of both species did not vary as fruit availability decreased by as much as 50%. Among gibbons, we observed dietary switching to fallback foods; in particular, there was a progressively greater reliance on figs, liana products, and unripe fruit. Orangutans relied heavily on unripe fruit and fracture-resistant bark and pith tissues. Despite these divergent fallback patterns, the stiffness of fruit mesocarp consumed by Hylobates and Pongo did not differ. We discuss canine and molar functional morphology with respect to dietary mechanics. Next, to contextualize these results, we discuss our findings with respect to forest structure. The rain forests of Southeast Asia have been described as having open, discontinuous canopies. Such a structure may inform our understanding of the ranging behavior and distinctive locomotion of apes in the region, namely richochetal brachiation and quadrumanous clambering. Our approach of integrating behavioral ecology with physical measures of food may be a powerful tool for understanding the functional adaptations of primates. Am J Phys Anthropol 140:716,726, 2009. © 2009 Wiley-Liss, Inc. [source] Clutch size in frugivorous insects as a function of host firmness: the case of the tephritid fly Anastrepha ludensECOLOGICAL ENTOMOLOGY, Issue 3 2003Francisco Díaz-Fleischer Abstract. 1.,Optimal clutch size theory predicts that individuals will oviposit the number of eggs that increases their fitness. In Anastrepha ludens Loew (Diptera: Tephritidae), females oviposit larger clutches in unripe (firm) fruits than in ripe (soft) fruits. The following hypotheses were tested: (1) Using fruit firmness as an indicator of fruit quality, A. ludens females vary the number of eggs per clutch every time they reach an oviposition decision. (2) Maximising offspring survival with respect to either unripe or ripe fruit requires placing large clutches in firm fruit and smaller clutches in soft fruit. 2.,Agar spheres were used as artificial hosts. Three agar concentrations resulted in three degrees of firmness. Mango fruits Mangifera indica L. served as natural hosts. Ripe and unripe fruits were used to test soft and firm host conditions respectively. Females laid significantly larger clutches in the firmer artificial hosts than in the softer hosts. They also laid significantly more eggs in artificial hosts without sugar than in hosts with sugar. Firm (unripe) mangoes also received significantly larger clutches than soft (ripe) mangoes. 3.,When an individual female was first presented with a firm artificial host, it laid a large clutch. If subsequently offered a soft host, the female laid a significantly smaller clutch. Finally, if again offered a firm host, clutch size was increased significantly. 4.,Possible trade-offs in offspring fitness were explored in ripe and unripe mangoes by measuring offspring egg-to-adult survival, pupal weight, mean adult longevity, and fecundity. Despite the fact that larval survival was greater in soft fruit than in firm fruit, parameters such as pupal weight, mean longevity, and fecundity of adults stemming from both fruit types did not differ significantly. 5.,A probable trade-off between high offspring mortality caused by host unsuitability and low offspring and adult mortality caused by parasitism and predation is discussed as the reason for the exploitation of sub-optimal hosts. [source] Foraging by fearful frugivores: combined effect of fruit ripening and predation riskFUNCTIONAL ECOLOGY, Issue 6 2006J. M. FEDRIANI Summary 1Plant defensive compounds and predation risk are main determinants of herbivore foraging, though empirical studies have seldom measured the combined effects of these two factors. By considering the interaction between the herb Helleborus foetidus and its main fruit and seed predator, the Wood Mouse Apodemus sylvaticus, we evaluated whether the defensive role against seed predators of compounds present in H. foetidus unripe fruits holds across a micro-landscape that differs in foraging costs (i.e. predation risk). 2First, we used standardized food patches that simulated fruiting H. foetidus plants to ascertain fruit preferences of captive mice. Then, by means of field experiments, we assessed the combined effects of fruit ripening and predation risk on foraging by free-ranging mice. 3Captive mice avoided plants with unripe fruit and avoided consuming unripe fruits within a particular plant. Free-ranging mice also avoided unripe fruits in safe microhabitats (rocky substrate), but not in risky microhabitats (bare ground) where few fruits were consumed. This unexpected result may be driven by predation risk experienced by mice foraging on H. foetidus fruits, and/or plant defensive compounds acting in a dose-dependent manner. 4Frugivorous mice responded to both chemical defences present in unripe H. foetidus fruits as well as to predation cost though such response was sequential. Plant defence compounds appeared to play a part in mouse foraging only after mice selected low predation risk microhabitats. 5Our study indicates that both digestive and ecological factors influence foraging decisions, which in turn affects pressures exerted by herbivores on plant populations. [source] Activity of trans -2-hexenal against Penicillium expansum in ,Conference' pearsJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2006F. Neri Abstract Aims:, To investigate the effects of trans -2-hexenal on blue mould disease, patulin content and fruit quality in ,Conference' pears. Methods and Results:, Fruits, wounded and inoculated with Penicillium expansum or non-inoculated, were exposed to trans -2-hexenal vapour treatment (12·5 ,l l,1) at 20°C. A greater reduction of decay was obtained by treatment application 24 or 48 h after inoculation, in contrast trans -2-hexenal application 2 h after inoculation was ineffective. Fruit storage temperature (,1°C) after treatment did not affect the antifungal activity. Although 2-h exposure to trans -2-hexenal was effective in reducing blue mould, an exposure of at least 8 h was required to reduce fruit patulin content. Treatments did not affect fruit physical,chemical characteristics. After 6 days at 20°C following exposure, trans -2-hexenal residue in treated fruits was less than the natural content of the compound in unripe fruits. Conclusions:,trans -2-Hexenal treatment is effective in the reduction of blue mould infections and patulin content in Conference pears when applied 24,48 h after pathogen inoculation. Significance and Impact of the Study:,trans -2-Hexenal could be a natural alternative to fungicides in the control of P. expansum infections. Further work is needed to study the methods and conditions avoiding the persistence of off-odours and off-flavours in pears after their exposure to trans -2-hexenal vapours. [source] Feeding habits of chimpanzees (Pan troglodytes), red-tail monkeys (Cercopithecus ascanius schmidti) and blue monkeys (Cercopithecus mitis stuhlmanii) on figs in Budongo Forest Reserve, UgandaAFRICAN JOURNAL OF ECOLOGY, Issue 2 2001Mnason Tweheyo Abstract Feeding habits of chimpanzees, red-tail and blue monkeys on figs (Ficus) were studied in compartment N3 of Budongo Forest Reserve, western Uganda, from September 1997 to March 1998. The aim was to examine the spatial and temporal foraging habits of chimpanzees, red-tail monkeys and blue monkeys on figs in the forest reserve. Both scan and focal sampling methods were used to assess the foraging habits of the primates. It was found that the primates fed on emerging leaves of Ficus mucuso Ficalho, F. varifolia Warb. and F. exasperata Vahl. They also preferred ripe fruits to emerging, young and unripe fruits. The primates spent 78% of the morning eating fruits and leaves and inhabited fig trees with fruits for about 4 h. Fig trees with ripe fruits attracted larger numbers of primate groups. It is concluded that information on the feeding habits of chimpanzees and monkeys is required in order to have a clear understanding of the social behaviour and pattern of movement of the primates and to assist in predicting the likely impacts of poor forest management, forest degradation and loss of food resources on their populations. Résumé On a étudié les habitudes alimentaires des chimpanzés, des red tails et des cercopithèques à diadème dans les figuiers (Ficus), dans le compartiment N3 de la Réserve Forestière de Budongo, à l'ouest de l'Ouganda, de septembre 1997 à mars 1998. Le but était d'examiner les habitudes alimentaires, dans l'espace et dans le temps, des chimpanzés, des red tails et des cercopithèques à diadème, dans les figuiers de la réserve forestière. On a utilisé les méthodes par scanner et par échantillonnage focal pour évaluer les habitudes alimentaires des primates. On a découvert que les primates se nourrissaient des jeunes feuilles de Ficus mucoso Ficalho, de F.varifolia Warb et de F.exasperata Vahl. Ils préféraient aussi les fruits mûrs aux fruits verts. Les primates passaient 78% de la matinée à manger des fruits et des feuilles et restaient environ 4 heures dans les figuiers qui avaient des fruits. Les figuiers dont les fruits étaient mûrs attiraient un plus grand nombre de groupes de primates. On en a conclu qu'il était nécessaire d'avoir des informations sur les habitudes alimentaires des chimpanzés et des singes pour bien comprendre le comportement social et schéma de déplacement des primates et pour aider à prévoir les impacts éventuels d'une piètre gestion forestière, de la dégradation de la forêt et de la disparition des ressources alimentaires sur leurs populations. [source] Screening for Alternative Antibiotics: An Investigation into the Antimicrobial Activities of Medicinal Food Plants of MauritiusJOURNAL OF FOOD SCIENCE, Issue 3 2010M.F. Mahomoodally ABSTRACT:, The present study was designed to evaluate the antimicrobial activities of 2 endemic medicinal plants; Faujasiopsis flexuosa,(Asteraceae) (FF) and Pittosporum senacia,(Pittosporaceae) (PS) and 2 exotic medicinal plants, Momordica charantia,(Cucurbitaceae) (MC) and Ocimum tenuiflorum,(Lamiaceae) (OT) that forms part of local pharmacopoeia of Mauritius and correlate any observed activity with its phytochemical profile. Aqueous and organic fractions of the leaves, fruits, and seeds of these plants were subjected to antimicrobial testing by the disc diffusion method against 8 clinical isolates of bacteria and 2 strains of fungus. It was found that MC, OT, and FF possessed antimicrobial properties against the test organisms. The MIC for MC ranged from 0.5 to 9 mg/mL and that of FF from 2 to 10 mg/mL and the lowest MIC value (0.5 mg/mL) was recorded for the unripe fruits of MC against E. coli. On the other hand, higher concentration of the unripe MC fruit extract of 9 mg/mL was needed to be effective against a resistant strain of Staphylococcus aureus,(MRSA). The antimicrobial effect against MRSA was lost upon ripening of the fruits. The methanolic extract of both MC and FF showed highest MIC values compared to the corresponding aqueous extract, which indicates the low efficacy and the need of higher doses of the plant extract. Phytochemical screening of the plants showed the presence of at least tannins, phenols, flavonoids, and alkaloids, which are known antimicrobial phyto-compounds. In conclusion, the observed antimicrobial properties would tend to further validate the medicinal properties of these commonly used endemic medicinal and food plants of Mauritius. [source] Craniodental mechanics and diet in Asian colobines: Morphological evidence of mature seed predation and sclerocarpyAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Daisuke B. Koyabu Abstract Folivory has been accepted as the general dietary pattern for colobines. However, recent ecological studies have revealed that extensive seed eating is found in some colobine species. The ripeness of foraged seeds is also reported to differ between seed eaters. As seeds are generally stress-limited and may pose greater mechanical demands, seed-eating species are predicted to exhibit morphological features adaptive for seed predation. In addition, species that feeds on seeds from unripe fruits with hard pericarp is predicted to exhibit increased leverage for anterior dentition. To test these hypotheses, we compared the craniodental morphology of seed-eating Asian colobines (Presbytis rubicunda and Trachypithecus phayrei) with those of species that rarely exploit seeds (Presbytis comata, Trachypithecus obscurus, and Semnopithecus vetulus). The results show that the seed-eating colobines possess a masticatory system with enhanced leverage at postcanine bite points. The sclerocarpic forager P. rubicunda also exhibits markedly greater masticatory leverage at anterior dental bite points, while the mature-seed-eating T. phayrei shows no such advantage for canine and incisor use. These observations suggest that P. rubicunda is well adapted to husking the resistant pericarps of unripe fruits, using the anterior dentition and to gain access to the immature seeds, whereas such sclerocarpic feeding behavior may be less important for T. phayrei. Our findings indicate that the distinctive craniodental variations of colobines may be linked to mature and/or immature seed eating and suggest the significance of seed predation for the evolution of colobine monkeys. Am J Phys Anthropol, 2010. © 2010 Wiley-Liss, Inc. [source] The feeding ecology and activity budget of proboscis monkeysAMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2009Ikki Matsuda Abstract A group of proboscis monkeys (Nasalis larvatus) consisting of an alpha-male, six adult females, and several immatures was observed from May 2005,2006. We collected over 1,968,hr of focal data on the adult male and 1,539,hr of focal data on the six females in a forest along the Menanggul River, Sabah, Malaysia. Availability and seasonal changes in plant species consumed by the focal monkeys were determined by vegetation surveys carried out across an area of 2.15,ha along 200,500,m trails in riverine forest. A total of 188 plant species were consumed by the focal monkeys. The activity budget of members of our study group was 76.5% resting, 19.5% feeding, and 3.5% moving. Young leaves (65.9%) and fruits (25.9%) accounted for the majority of feeding time. Over 90% of fruit feeding involved the consumption of unripe fruits and in the majority of case both the fruit flesh and seeds were eaten. Although fruit eating was rare in some months, during other times of the year time fruit feeding exceeded the time devoted to young leaves. We found that monthly fruit availability was positively related to monthly fruit eating and feeding activity, and seasonal fluctuations in dietary diversity were significantly affected by fruit eating. These results suggest that fruit availability and fruit-eating behaviors are key factors that influence the activity budget of proboscis monkeys. Earlier assumptions that colobine monkeys are obligate folivores do not apply well to proboscis monkeys and certain other colobines. Our findings may help contribute to a better understanding of the dietary adaptations and feeding ecology of Asian colobines. Am. J. Primatol. 71:478,492, 2009. © 2009 Wiley-Liss, Inc. [source] | ||||||||||