To the extent that geography correlates with particular environmental parameters, the geographical distribution of phylogenetically related social and nonsocial organisms should shed light on the conditions that lead to sociality versus nonsociality. Social spiders are notorious for being concentrated in tropical regions of the world, occupying a set of habitats more restricted than those available to the phylogenetic lineages in which they occur. Here we document a parallel pattern involving elevation in the spider genus Anelosimus in America and describe the biology of a newly discovered social species found at what appears to be the altitudinal edge of sociality in the genus. We show that this is a cooperative permanent-social species with highly female-biased sex ratios but colonies that are one to two orders of magnitude smaller than those of a low-elevation congener of similar body size. We suggest that the absence of subsocial Anelosimus species in the lowland rain forest may be due to an increased probability of maternal death in this habitat due to greater predation and/or precipitation, while absence of a sufficient supply of large insects at high elevations or latitudes may restrict social species to low- to midelevation tropical moist forests. We refer to these as the "maternal survival" and "prey size" hypotheses, respectively, and suggest that both in combination may explain the geographical distribution of sociality in the genus.

Correlations in behavioural traits across time, situation and ecological context (i.e. ‘behavioural syndromes’ or ‘personality’) have been documented for a variety of behaviours, and in diverse taxa. Perhaps the most controversial inference from the behavioural syndromes literature is that correlated behaviour may act as an evolutionary constraint and evolutionary change in one’s behaviour may necessarily involve shifts in others. We test the two predictions of this hypothesis using comparative data from eighteen populations of the socially polymorphic spider, Anelosimus studiosus (Araneae, Theriidae). First, we ask whether geographically distant populations share a common syndrome. Second, we test whether population differences in behaviour are correlated similarly to within‐population trait correlations. Our results reveal that populations separated by as much as 36° latitude shared similar syndromes. Furthermore, population differences in behaviour were correlated in the same manner as within‐population trait correlations. That is, population divergence tended to be along the same axes as within‐population covariance. Together, these results suggest a lack of evolutionary independence in the syndrome’s constituent traits.

We studied 19 different tropical fruits traditionally consumed in the coastal lowlands of Ecuador to determine their chemical composition and antioxidant activity. Carambola (Averrhoa carambola L.) had the highest total phenolic, flavonoid, and total antioxidant capacity values, whereas guava fruits (Psidium guajava L.) had the highest vitamin C values. The main organic acids identified were lactic, citric, and acetic acids, and the highest amount of lactic acid was found in soursop fruits (Annona muricata L.), whereas Ecuadorian ivory palm (Phytelephas aequatorialis Spruce) and guava fruits had the highest acetic acid content. Guava also had the highest citric acid content; the highest concentration of oxalic acid was found in carambola. In terms of sugar content, giant granadilla (Passiflora quadrangularis L.) had the highest values of glucose, and red mombin (Spondias mombin L.) had the largest values for fructose and guava for sucrose. Chili pepper (Capsicum chinense Jacq) proved to be the main source of carotenoids, lutein, and β-carotene, anthocyanins, and vitamin C. The results here increase our knowledge regarding the composition of the main fruits consumed on the west coast of Ecuador to facilitate recommendations as potential sources of health-promoting compounds.

BACKGROUND: Andean blackberries (Rubus glaucus Benth) and Andean blueberries (Vaccinium floribundum Kunth) are wild berries consumed and commercialised by the indigenous people of the Andean regions of Ecuador. OBJECTIVE: This study aims to determine the chemical composition and the ability of A. blackberries and A. blueberries to protect human dermal fibroblast (HDFa) against cytotoxic oxidative damage. METHODS: Total phenolic, flavonoid, anthocyanins and tannins content were determined spectrophotometrically, while vitamin C and carotenes were determined by HPLC. Total antioxidant capacity was determined by the Ferric Reducing Antioxidant Power (FRAP) assay, the hydrogen peroxide scavenging activity and the DPPH and superoxide radical scavenging capacity. HDFa was pre-treated with A. blackberries or A. blueberries crude extract, subjected to a model of oxidative stress using the stressor 2,2’-azobis(2-amidinopropane) dihydrochloride (AAPH) and the markers of cell cytotoxic damage (intracellular ROS levels, catalase, superoxide dismutase and glutathione activities, lipid peroxidation, protein oxidation and ATP and nitrite levels) were determined. RESULTS: A. blueberries showed significantly high values of total phenolic, flavonoid, anthocyanin, lutein tannin content, whilst A. blackberries showed the highest values of vitamin C and β-carotene. After HDFa was pre-incubated with crude extracts of A. blackberries and A. blueberries, the markers of oxidative damage were significantly improved compared with the stressed cells group. In all cases, crude extract of A. blueberries showed a higher protective effect compared to A. blackberries. CONCLUSION: A. blackberry and A. blueberry attenuated the oxidative damage in HDFa showing that both fruits may represent a relevant source of bioactive compounds with promising benefits for human health.

No abstract