Bird preferences for fruit size, but not color, vary in accordance with fruit traits along a tropical elevational gradient.

Birds constitute one of the most important seed dispersal agents globally, especially in the tropics. The feeding preferences of frugivorous birds are, therefore, potentially of great ecological importance. A number of laboratory-based and observational studies have attempted to ascertain the preferences of certain bird species for certain fruit traits. However, little attention has been paid to community-wide preferences of frugivorous birds and the impact this may have on fruit traits on a broader scale. Here, we used artificial fruits of different colors and sizes to investigate community-wide fruit trait preferences of birds at three sites along an elevational gradient in Papua New Guinea. We recorded attack rates on artificial fruits as visible impressions made by a bird's beak during a feeding attempt. We also measured the colors and sizes of real fruits at each site, and the gape widths of frugivorous birds, allowing for comparisons between bird feeding preferences and bird and fruit traits. Regardless of elevation, red and purple fruits were universally preferred to green and attacked at similar rates to one another, despite strong elevational patterns in real fruit color. However, elevation had a significant effect on fruit size preferences. A weak, non-significant preference for large fruits was recorded at 700 m, while medium fruits were strongly preferred at 1700 m and small fruits at 2700 m. These patterns mirror those of both real fruit size and frugivorous bird gape width along the gradient, suggesting the potential for selective pressure of birds on fruit size at different elevations.

Induction of apoptosis in the gonads of Mytilus edulis by metformin and increased temperature, via regulation of HSP70, CASP8, BCL2 and FAS.

Pharmaceutically active compounds have been considered contaminants of emerging concern, in response to evidence that these substances may adversely affect aquatic organisms. Here we expose mussels for 7 days to metformin, the most commonly prescribed anti-diabetes treatment, at a concentration of 40 µg/L and a high temperature of 20 °C. The apoptosis-related genes HSP70, CASP8, BCL2 and FAS showed variation in expression in gonadal tissue. The results suggest that complex interactions between these genes are modulating the onset of apoptotic changes such as atresia and follicle degeneration. The temperature induced apoptosis may be initiated by overexpression of CASP8. Conversely, metformin may induce apoptosis by suppressing the anti-apoptotic gene BCL2, thus promoting the process. Interestingly, apoptosis and follicle degeneration are likely FAS-mediated, following the synergistic effect of metformin and temperature. The potential of metformin to act as a non-traditional EDC, due to its impact on the reproductive system in mussels is discussed.

High concentrations of paracetamol in effluent dominated waters of Jakarta Bay, Indonesia.

The occurrence of several aquatic contaminants, including pharmaceuticals, were investigated in seawater samples collected from effluent-dominated sites in Indonesia: 4 sites in Jakarta Bay and one on the north coast of Central Java. The data presented in this preliminary study provide a snapshot of seawater quality in these areas. Results show that nutrient parameters exceeded the Indonesian Standard Quality of Seawater limits, and some metals were also present. Interestingly, high concentrations of paracetamol were detected at Angke (610 ng/L) and Ancol (420 ng/L), both in Jakarta Bay. To date, this is the first study to report the presence of paracetamol (acetaminophen) in the coastal waters around Indonesia. The high concentrations detected, compared to other levels reported in scientific literature, raise concerns about the environmental risks associated with long-term exposure and, especially, the impact on nearby shellfish farms. Given pharmaceuticals' consideration as emerging contaminants, these data suggest further investigations are needed.

Long-term exposure of marine mussels to paracetamol: is time a healer or a killer?

Pharmaceuticals pose a major threat to the marine environment, and several studies have recently described their negative effects on marine organisms. Pharmaceutical compounds are constantly being released into aquatic ecosystems, and chronic exposure, even at low concentrations, may have a major impact on marine organisms. The purpose of the present study is to evaluate the biological changes induced by one of the most widely used pharmaceuticals-paracetamol-in the blue mussel Mytilus edulis, after a long-term exposure at environmentally relevant concentrations. We present our data alongside and in comparison with results from a previous short-term exposure, to demonstrate the significance of exposure period on the effects of paracetamol in adult blue mussels. After 24 days of laboratory exposure, seven potential target genes were selected to examine toxicological effects in mussels' gonads and possible disruptive effects on reproductive processes. The results show the modulation of some important reproduction-related genes: estrogen receptor-2 (ER2), vitelline envelope zona pellucida domain-9 (V9), and vitellogenin (VTG). Variations in mRNA expression of four other genes involved in apoptosis (HSP70, CASP8, BCL2, and FAS) are also highlighted. Histopathological alterations caused by paracetamol, together with neutral red retention time response in mussels' hemocytes, are presented herein. Overall, this study highlights the exacerbated effects of low concentration of paracetamol after chronic exposure, similar to the damage induced by higher concentrations in a short exposure scenario, thus emphasizing the importance of length of exposure period when studying the effects of this substance. Additionally, this study also discusses the potential of paracetamol to inflict several major changes in the reproductive system of mussels and thus possibly affect the survival of populations.

Effects of short-term exposure of paracetamol in the gonads of blue mussels Mytilus edulis.

A growing body of literature suggests that pharmaceutical contamination poses an increasing risk to marine ecosystems. Paracetamol or acetaminophen is the most widely used medicine in the world and has recently been detected in seawater. Here, we present the results of 7 days' exposure of blue mussel adults to 40 ng/L, 250 ng/L and 100 µg/L of paracetamol. Histopathology shows that haemocytic infiltration is the most observed condition in the exposed mussels. The mRNA expression of VTG, V9, ER2, HSP70, CASP8, BCL2 and FAS in mussel gonads present different patterns of downregulation. VTG and CASP8 mRNA expression show downregulation in all exposed mussels, irrespective of sex. The V9, HSP70, BCL2 and FAS transcripts follow a concentration-dependent variation in gene expression and may therefore be considered good biomarker candidates. ER2 mRNA expression shows a downregulated trend, with a clearer dose-response relationship in males. In conclusion, this study suggests that paracetamol has the potential to alter the expression of several genes related to processes occurring in the reproductive system and may therefore impair reproduction in blue mussels.