Evaluation of cytotoxic effects of plants is as essential as their phytochemical appraisal in medicinal botany and drug discovery. In this study, the cytotoxic activity of the methanol, ethanol, and crude aqueous extracts of the plant Betel Vine Piper betle Linn. under the family Piperaceae was evaluated using the brine shrimp lethality (BSL) assay. Cytotoxic activity of P. betle was assessed based on lethality concentration. Brine shrimp eggs were hatched, and 10 resulting nauplii were added to the diluted test solutions at varying concentrations -5 μg/mL, 50 μg/mL, and 500 μg/mL. Surviving Artemia salina Leach shrimp nauplii were counted after 24 hours and lethality concentration was determined. Maximum mortality of the brine shrimp was observed at the highest treated-concentration whereas least mortality at the lowest treated-concentration. Ethanol and methanol crude extracts showed significant cytotoxic activity with LC 50 values of 23.65 μg/mL and 85.50 μg/mL, respectively, which indicated the presence of potent cytotoxic components of the plant. Hence, P. betle is found to be containing cytotoxic compounds but this result does not necessarily suggest complete toxicity of the plant because it may also suggest potential antitumor or anticancer activities.

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Interactions of species have been recognized to play an important role in the structure and functioning of the environment. However, the exact mechanism is not well understood particularly under shifting environmental conditions like pollution. To determine the effects of pollutants/contaminants on the fitness of two soil nematodes (Acrobeloides nanus and Bursilla monhystera) under pristine and polluted condition, we performed experimental set-ups (monoculture and combined cultures) and exposed the organisms to varying sublethal cadmium (Cd) concentrations (0 mg/L, 1.4 mg/L and 1.9 mg/L). In monoculture, results showed continuous increase in the abundances of A. nanus and B. monhystera in non-polluted condition. Abundance of A. nanus remained increased in polluted condition, however, B. monhystera responded negatively to increasing Cd concentrations. In combination, results in non-polluted condition showed that B. monhystera exhibited a negative effect on the abundance of A. nanus, suggesting that B. monhystera is a stronger competitor than A. nanus. However, a shift in abundance pattern was observed when both species were exposed to pollutants particularly on the positive effect by A. nanus on B. monhystera which implies that sublethal Cd concentrations can potentially alter species interactions. Thorough assessment of nematode interactions is essential in explaining patterns of community structure in disturbed systems and determining proper functioning in the ecosystem.

Difference between sexes was quantified in this study using outline basedgeometric morphometric analysis on the shape of the primary wing and tail feathers of the sky blue strain of parakeet bird Melopsittacus undulatus (Shaw, 1805). Results of Discriminant Function Analysis (DFA) and Principal Component Analysis (PCA) utilizing the coefficients derived from Elliptic Fourier Analysis (EFA) consistently showed that sexual dimorphism is present in the said species with differences primarily explained by the variations in the tip and outline of the flight feathers. Females generally have slightly rounded tip and partially curved (inward) feather outline while males have feathers with slightly pointed tip and more or less straight feather outline. However, no difference between sexes was observed in the shape of tail feathers. It is suggested that based from this study, a more complete understanding and proper identification on the biological basis of the observed wing shape differences are needed which could be elemental in the proper and effective conservation of this species.

Leptocorisa varicornis (F.) (1803) rice bug is a serious pest of rice. Misidentification of this pest had led to non-effective management strategies resulting to possible emergence of insecticide resistance. Proper identification of this species is necessary in developing effective management strategies against this pest, and correct identification needs accurate examination of the insect's morphology. Geometric morphometrics (GM) statistically analyzes shape variability allowing better understanding of the nature and variability of the insect in relation to the evolvability of characters and its possible implications to adaptability of the organism. This study made use of GM to determine forewing shape variability between sexes and across populations of L. varicornis (F.) from selected localities in Northern Mindanao, Philippines. Exploratory results initially showed that variations between sexes were generally characterized by differences in overall shape of forewing, apex and wing base. Variations across populations were associated largely with differences in overall forewing shape, contour of inner margin, and shape of wing base. Series of confirmatory tests obtained highly significant results, which all confirmed presence of intersexual and interpopulation variations in L. varicornis. Environmental stressors like seasonal cropping, flood and application of pesticides might influence differences in forewings of rice bugs since rice bugs have to fly to long distance after cropping or change location when existing habitat conditions are no longer suitable for their survival. Thorough understanding of the biological basis of the observed variations is essential for the effective control against this species.