Complex Recent History Research Articles

Genetic history and stock identity of beluga whales in Kotzebue Sound

We investigate the recent history and stock identity of beluga whales (Delphinapterus leucas) in Kotzebue Sound in the Chukchi Sea, a region long frequented by large numbers of belugas in summer until their near disappearance in the 1980s. Wide variation in numbers since then suggests a complex recent history that hinders recovery efforts. Analysis of teeth sampled during the historical (pre-decline) era using ancient DNA (aDNA) methods found that the original Kotzebue Sound whales were differentiated for mitochondrial DNA (mtDNA) from other summering concentrations across the Pacific Arctic revealing a demographically distinct subpopulation where long-established migratory culture likely facilitated population divergence. Analysis of microsatellite (nDNA) and mtDNA markers in belugas from the contemporary (post-decline) era revealed that whales from other stocks likely visited Kotzebue Sound, including during two low ice years when relatively large numbers of whales were present. Some mtDNA lineages were found only in Kotzebue Sound, with one recorded in both the historical and contemporary eras. Exclusion tests found a number of whales in Kotzebue Sound during the contemporary era that had nDNA genotypes unlikely to arise in other contemporary stocks in the Pacific Arctic. Our findings indicate that the Kotzebue Sound belugas comprised a unique stock of which a few remnants likely still co-occur with belugas from other larger stocks. We recommend that the US government work through the co-management process to greatly reduce or eliminate the taking of belugas, especially adult females, likely to belong to the Kotzebue Sound stock, until they recover.

Dis]rupting, [mis]understanding, [un]learning and [re]membering—Lerato Shadi, Hamedine Kane and Euridice Zaituna Kala

Ordinary activities, performed by billions of persons all over the globe every day in a myriad situations feature in live art interventions by Lerato Shadi, Hamedine Kane and Euridice Zaituna Kala, respectively South African, Mauritanian/Senegalese and Mozambican. The unobtrusive and intimate nature of their gestures may strike the reader as incommensurable with what is habitually understood by ‘knowledge production’ in institutionalized situations. Their gestures seem paradoxically counter-performative in the sense that they are not geared to ‘performance’ as understood in the neo-liberal corporate world, yet they are intimately pertinent to knowledge production as well as to contemporary art. This text suggests that critically positioned knowledge is acquired via bodily action as the artist’s body functions as a vehicle for memory, for perceiving by acting. Awareness of the body as a political entity brings awareness of the embodied specificity of knowledge and the egalitarian nature of intelligences. The processes of individuation set in motion are of particular interest to urgent Earth-wide concerns, namely the crucial need to [un]learn former thinking patterns preventing us from thinking outside of the colonial mind-set. Protesting the political circumstance of the processes determining the hegemonic standardization of knowledge is not an African prerogative, but, given the complex recent history of the continent, the political crystallizes here in particularly telling ways. In the three artist’s actions the everydayness of knowing or not knowing, the wisdom of [un]knowing and of misunderstanding is re-activated, re-cognized and re-membered in continual flux. They perform everyday resistance and disruption though commonplace gestures acted out in situations where collective ways of [un-]knowing may come about, as [un-]learning is discovered as a gesture of [re-]membering.

Phylogeography of the Cran’s bullyGobiomorphus basalis(Gobiiformes: Eleotridae) and an analysis of species boundaries within the New Zealand radiation ofGobiomorphus

AbstractNew Zealand has a complex recent history of climatic and tectonic change that has left variable signatures in the geographic distribution and genetic structure of the region’s flora and fauna. To identify concordant patterns, a broad range of taxa must be examined and compared. In New Zealand’s North Island, a consensus is forming as to the dominant biogeographic barriers in the region although obligate freshwater taxa have not been considered in this framework. We use single-nucleotide polymorphisms to investigate phylogeography in the widespread obligate freshwater fish Gobiomorphus basalis on the North Island. Phylogeographic patterns within G. basalis reveal biogeographic disjunctions that are in some ways consistent and in other ways at odds with established patterns, providing insight into the processes that have shaped the islands’ biogeography. We also use phylogeography to delineate species boundaries within the entire New Zealand radiation of Gobiomorphus and find that it contains several morphologically cryptic species. We resolve two clades within G. basalis that correspond to areas north and south of the Taupo Volcanic Zone. We confirm the distinctiveness of Gobiomorphus alpinus relative to Gobiomorphus cotidianus, as well as the presence of two lineages within Gobiomorphus breviceps that were previously identified based on mitochondrial data.

The flickering nuclear activity of Fornax A

We present new observations of Fornax A taken at ∼1 GHz with the MeerKAT telescope and at ∼6 GHz with the Sardinia Radio Telescope (SRT). The sensitive (noise ∼16 μJy beam−1), high-resolution (≲10″) MeerKAT images show that the lobes of Fornax A have a double-shell morphology, where dense filaments are embedded in a diffuse and extended cocoon. We study the spectral properties of these components by combining the MeerKAT and SRT observations with archival data between 84 MHz and 217 GHz. For the first time, we show that multiple episodes of nuclear activity must have formed the extended radio lobes. The modelling of the radio spectrum suggests that the last episode of injection of relativistic particles into the lobes started ∼24 Myr ago and stopped 12 Myr ago. More recently (∼3 Myr ago), a less powerful and short (≲1 Myr) phase of nuclear activity generated the central jets. Currently, the core may be in a new active phase. It appears that Fornax A is rapidly flickering. The dense environment around Fornax A has lead to a complex recent merger history for this galaxy, including mergers spanning a range of gas contents and mass ratios, as shown by the analysis of the galaxy’s stellar- and cold-gas phases. This complex recent history may be the cause of the rapid, recurrent nuclear activity of Fornax A.

Genetic structure and recovery of white‐tailed deer in Missouri

ABSTRACTThe white‐tailed deer (Odocoileus virginianus) of Missouri have undergone changes in the past 100 years. From a historical estimate of 700,000 individuals, deer were nearly extirpated from the state following overexploitation in the late 1800s. Despite this, deer have since undergone a rapid expansion to the current population of 1.4 million. Because of this complex recent history, we sought to understand the levels and distribution of genetic diversity in deer across Missouri. We genotyped 751 deer at 10 microsatellite loci and used genetic distance metrics and Bayesian clustering analyses to identify distinct genetic groups. We also sequenced the mitochondrial control region from a subset (n = 248) of deer to identify historical lineages. We found high levels of nuclear marker diversity (HE = 0.818) and low, but statistically significant, levels of differentiation among regions. The high level of mitochondrial diversity (48 haplotypes; haplotype diversity = 0.621–0.964) is reflected in a haplotype network that suggests the persistent signature of translocated lineages. Overall, the white‐tailed deer of Missouri now represent a highly diverse population with no indication that there are barriers to gene flow. This will be an important consideration for the management of disease resistance and spread throughout the state. © 2018 The Wildlife Society.

The Genetic Legacy of Religious Diversity and Intolerance: Paternal Lineages of Christians, Jews, and Muslims in the Iberian Peninsula

Most studies of European genetic diversity have focused on large-scale variation and interpretations based on events in prehistory, but migrations and invasions in historical times could also have had profound effects on the genetic landscape. The Iberian Peninsula provides a suitable region for examination of the demographic impact of such recent events, because its complex recent history has involved the long-term residence of two very different populations with distinct geographical origins and their own particular cultural and religious characteristics—North African Muslims and Sephardic Jews. To address this issue, we analyzed Y chromosome haplotypes, which provide the necessary phylogeographic resolution, in 1140 males from the Iberian Peninsula and Balearic Islands. Admixture analysis based on binary and Y-STR haplotypes indicates a high mean proportion of ancestry from North African (10.6%) and Sephardic Jewish (19.8%) sources. Despite alternative possible sources for lineages ascribed a Sephardic Jewish origin, these proportions attest to a high level of religious conversion (whether voluntary or enforced), driven by historical episodes of social and religious intolerance, that ultimately led to the integration of descendants. In agreement with the historical record, analysis of haplotype sharing and diversity within specific haplogroups suggests that the Sephardic Jewish component is the more ancient. The geographical distribution of North African ancestry in the peninsula does not reflect the initial colonization and subsequent withdrawal and is likely to result from later enforced population movement—more marked in some regions than in others—plus the effects of genetic drift.