Rapid and repeatable host plant shifts drive reproductive isolation following a recent human-mediated introduction of the apple maggot fly,Rhagoletis pomonella

Ecological speciation via host-shifting is often invoked as a mechanism for insect diversification, but the relative importance of this process is poorly understood. The shift of Rhagoletis pomonella in the 1850s from the native downy hawthorn, Crataegus mollis, to introduced apple, Malus pumila, is a classic example of sympatric host race formation, a hypothesized early stage of ecological speciation. The accidental human-mediated introduction of R. pomonella into the Pacific Northwest (PNW) in the late 1970s allows us to investigate how novel ecological opportunities may trigger divergent adaptation and host race formation on a rapid timescale. Since the introduction, the fly has spread in the PNW, where in addition to apple, it now infests native black hawthorn, Crataegus douglasii, and introduced ornamental hawthorn, Crataegus monogyna. We use this “natural experiment” to test for genetic differentiation among apple, black, and ornamental hawthorn flies co-occurring at three sympatric sites. We report evidence that populations of all three host-associations are genetically differentiated at the local level, indicating that partial reproductive isolation has evolved in this novel habitat. Our results suggest that conditions suitable for initiating host-associated divergence may be common in nature, allowing for the rapid evolution of new host races when ecological opportunity arises.     

Phytotoxic effect of simulated acid rain on black gram

A pot experiment was carried out to observe the response of black gram (Phaseolus mungo L.) to acid rain. The plants were exposed to different concentrations of simulated acid rain (pH 5, 4, 3). The symptoms such as injuries and necrotic spots appeared on the leaves. Plant growth, yield and photosynthetic pigments were suppressed greatly in all the treatments. The suppressions were directly proportional to the exposure levels of acid rain on the plants.     

Effect of Lysine Addition on Growth of Black Iguana (Ctenosaura pectinata)

The effects of the addition of lysine to commercial feed given to captive black iguana (Ctenosaura pectinata) were evaluated in terms of growth and feed digestibility. Twenty‐eight‐day‐old black iguana with an initial weight of 5.5 ± 0.3 g were housed individually in cages measuring 45 × 45 × 45 cm. The experiment lasted 150 days. The ambient temperature ranged from 28 to 35°C with a relative humidity of 60 to 95%. Treatments consisted of the addition of different percentages of lysine to the feed (0.0, 0.1, 0.2, and 0.3%, dry matter [DM] base). There was a linear response (P < 0.01) in daily gain (68, 112, 118, and 151 mg/d) and daily intake (251, 289, 297, and 337 mg/d) for levels from 0 to 0.3%, respectively, as well in the growth in head size, snout–vent length, and total length. The digestibility of DM, neutral detergent fiber, and acid detergent fiber were reduced linearly (P < 0.01) as lysine levels increased. Intake and digestibility were negatively correlated (r = –0.74; P < 0.001). It is concluded that the addition of lysine to the black iguana diet in the first months of life is important to stimulate growth and intake. Zoo Biol 32:277–280, 2013. © 2012 Wiley Periodicals, Inc.     

Geometric morphometrics as a tool for interpreting evolutionary transitions in the black fly wing (Diptera: Simuliidae)

A geometric morphometric analysis was conducted on wing‐vein landmarks on exemplar species of the family Simuliidae of the following genera: Parasimulium, Gymnopais, Twinnia, Helodon, Prosimulium, Greniera, Stegopterna, Tlalocomyia, Cnephia, Ectemnia, Metacnephia, Austrosimulium, and Simulium. Generalized least squares superimposition was performed on landmarks, followed by a principal component analysis on resulting Procrustes distances. Patterns of shape change along the principal component axes were visualized using the thin‐plate spline. The analysis revealed wing shape diversity through (1) the insertion points of the subcosta and R₁, resulting in the terminus of the costa exhibiting a trend towards a more apical position on the wing, and (2) the insertion point of the humeral cross vein, resulting in the anterior branch of the media exhibiting a trend toward a more basal position on the wing. Canonical variates analysis of Procrustes distances successfully assigned all exemplar species into their a priori taxonomic groupings. The diversity in wing shape reveals a trend towards decreased length of basal radial cell and increased costalization of anterior wing veins in the evolutionary transition from plesiomorphic prosimuliines to more derived simuliines. The functional significance of these evolutionary transitions is discussed. © 2013 The Linnean Society of London     

‘I'm black and I'll always be that way’: black identities through the lens of interracial intimacy

Early research on black racial identity development cautioned that close relationships with whites signalled an alienation from blackness and a subconscious acceptance that ‘white is right’. These assumptions mirrored popular media and political discourse suggesting that romantic relationships outside of one's racial group reflect a devalued or inauthentic racial self. More recent scholarly research presents a mixed picture about the role of interracial intimacy on black racial identities. Using in-depth qualitative narratives with forty-two interracially partnered African Americans, this article explores whether interracial intimacy recasts the meaning or intensity of black racial identities. Findings affirm that black racial identities are heterogeneous – some partners experienced blackness as a central, fundamental identity while others possessed ambivalent attachments to blackness. Across these experiences, however, adult interracial intimacy had at most an incremental influence on racial identity. Interracial contact during adolescence was far more influential because it allowed blacks to develop dimensions of white cultural identity.     

Ethnic identity on display: West Indian youth and the creation of ethnic boundaries in high school

The black immigrant population in New York City has grown exponentially since 1990, such that West Indians now compose the majority of the black population in several neighbourhoods. This article examines how this ethnic density manifests among youth in high school, and how it has influenced ethnic identity formation among second-generation West Indians. My findings are based on twenty-four interviews and eight months of participant observation in two Brooklyn high schools from 2003 to 2004. The results show that in both schools, Caribbean island identities have become a ‘cool’ commodity within peer groups. Further, although it was important to express pride in one's island identity, these young people often blurred their national origin boundaries by drawing on Jamaican popular culture as way of projecting a unified ‘West Indian identity’. The research also uncovers evidence of a de-stigmatization of Haitianness as a way to incorporate them as cultural insiders into the larger Caribbean collective.     

Why aren't there more black football managers?

Abstract

The number of black and minority ethnic (BME) managers in English professional association football, or soccer, has been stable for nearly ten years: there are usually between two and four (out of a possible ninety two). Yet black players regularly make up more than a quarter of professional club squads. The reasons for this apparent under-representation are explored among 1,000 football fans, including players and ex-players, both white and BME. Opinions were solicited via an online research platform http://www.topfan.co.uk, designed and executed by the authors. The findings indicate 56 per cent of respondents believe racism operates at the executive levels of football, i.e. the boardroom. While some accuse club owners and directors of deliberate discrimination, most suspect a form of unwitting or institutional racism in which assumptions about black people's capacities are not analysed and challenged and so continue to circulate. Among the possible remedies to this is the American National Football League's Rooney Rule, which mandates BME candidates’ inclusion on shortlists for senior coaching positions. A third of participants in the research approved of this type of initiative. While black managers are scarce when compared to the number of black players in professional football, their presence is actually an accurate reflection of their number in the total British population. So is the dearth of black managers an under-representation?     

Chocolate cities: A brief note from a race and capitalism perspective

Marcus Hunter and Zandria Robinson have provided us with an innovative methodology for analysing “maps” of African Americans’ lived political, social and cultural experiences past and present. Their powerful innovation is creating maps of the black experience based on black people’s lived experience. They argue that carefully tracing spatially blacks’ political, social and cultural patterns over time leads one to the conclusion that the shared experiences of blacks throughout the polity (and indeed throughout the Diaspora) have far more in common than not. I argue that we can better understand not only the maps that black people have created, but also chocolate cities themselves by using an analytical framework that integrates the analysis of the lived experience of black people with a structural analysis that interrogates the articulation of white supremacy, capitalism and patriarchy. This framework is related to the developing research into racial capitalism that is now being conducted globally.