The modern life sciences Alt, Christina
Virginia Woolf and the Study of Nature,
07/2010
Book Chapter
In the late nineteenth century, the long domination of taxonomic natural history was brought to an end by the combined impact of evolutionary theory and the new biology of the laboratory. As the ...twentieth century began, ethology and ecology also emerged as recognised disciplines and added a further dimension to the study of nature. In contrast to taxonomic natural history, which focused on the description of organisms for purposes of identification and systematic arrangement, these emerging disciplines sought a wider and deeper understanding of nature through consideration of the origins and evolution of life, the internal make-up and functioning of organisms, the behaviour of living things, and the interrelationships occurring among organisms in a shared environment.Woolf's interest in developments in the study of nature is demonstrated by her allusions to the work of nature writers, scientists, and science popularisers. In addition to her well-documented familiarity with and respect for Darwin's work, she refers in her fiction to T. H. Huxley and to Gregor Mendel's laws of inheritance (MEL 62; VO 55; MD 85, 33; ND 385). She was acquainted with Jean-Henri Fabre's work on insect behaviour; she alludes to Richard Jeffries; and she read and reviewed W. H. Hudson's nature writing, expressing admiration for both his literary style and his approach to the natural world. Over the winter of 1931–2, she ‘dipped into The Sciences of Life sic’, a survey of approaches to the study of nature by H. G. Wells, Julian Huxley, and G. P. Wells (Liv: 418).
In Europe, the Neolithic transition (8,000-4,000 B.C.) from hunting and gathering to agricultural communities was one of the most important demographic events since the initial peopling of Europe by ...anatomically modern humans in the Upper Paleolithic (40,000 B.C.). However, the nature and speed of this transition is a matter of continuing scientific debate in archaeology, anthropology, and human population genetics. To date, inferences about the genetic make up of past populations have mostly been drawn from studies of modern-day Eurasian populations, but increasingly ancient DNA studies offer a direct view of the genetic past. We genetically characterized a population of the earliest farming culture in Central Europe, the Linear Pottery Culture (LBK; 5,500-4,900 calibrated B.C.) and used comprehensive phylogeographic and population genetic analyses to locate its origins within the broader Eurasian region, and to trace potential dispersal routes into Europe. We cloned and sequenced the mitochondrial hypervariable segment I and designed two powerful SNP multiplex PCR systems to generate new mitochondrial and Y-chromosomal data from 21 individuals from a complete LBK graveyard at Derenburg Meerenstieg II in Germany. These results considerably extend the available genetic dataset for the LBK (n = 42) and permit the first detailed genetic analysis of the earliest Neolithic culture in Central Europe (5,500-4,900 calibrated B.C.). We characterized the Neolithic mitochondrial DNA sequence diversity and geographical affinities of the early farmers using a large database of extant Western Eurasian populations (n = 23,394) and a wide range of population genetic analyses including shared haplotype analyses, principal component analyses, multidimensional scaling, geographic mapping of genetic distances, and Bayesian Serial Simcoal analyses. The results reveal that the LBK population shared an affinity with the modern-day Near East and Anatolia, supporting a major genetic input from this area during the advent of farming in Europe. However, the LBK population also showed unique genetic features including a clearly distinct distribution of mitochondrial haplogroup frequencies, confirming that major demographic events continued to take place in Europe after the early Neolithic.
The association between macrocephaly and autism spectrum disorder (ASD) suggests that the mechanisms underlying excessive neural growth could contribute to ASD pathogenesis. Consistently, neural ...progenitor cells (NPCs) derived from human induced pluripotent stem cells (hiPSCs) of ASD individuals with early developmental brain enlargement are inherently more proliferative than control NPCs. Here, we show that hiPSC-derived NPCs from ASD individuals with macrocephaly display an altered DNA replication program and increased DNA damage. When compared with the control NPCs, high-throughput genome-wide translocation sequencing (HTGTS) demonstrates that ASD-derived NPCs harbored elevated DNA double-strand breaks in replication stress-susceptible genes, some of which are associated with ASD pathogenesis. Our results provide a mechanism linking hyperproliferation of NPCs with the pathogenesis of ASD by disrupting long neural genes involved in cell-cell adhesion and migration.
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•NPCs derived from macrocephalic ASD patients exhibit replication stress•Replication stress induces replication-transcription conflicts•Replication stress induces DSB hotspots in genes in human NPCs•ASD-derived NPCs show aberrant adherens junctions, apical polarity, and migration
Replication stress poses threats to genome stability. Wang et al. show that macrocephalic ASD patient-specific neural progenitor cells display increased DNA damage in a group of long neural genes vulnerable to replication stress, some of which are associated with the pathogenesis of ASD.
The processes that shaped modern European mitochondrial DNA (mtDNA) variation remain unclear. The initial peopling by Palaeolithic hunter-gatherers ~42,000 years ago and the immigration of Neolithic ...farmers into Europe ~8000 years ago appear to have played important roles but do not explain present-day mtDNA diversity. We generated mtDNA profiles of 364 individuals from prehistoric cultures in Central Europe to perform a chronological study, spanning the Early Neolithic to the Early Bronze Age (5500 to 1550 calibrated years before the common era). We used this transect through time to identify four marked shifts in genetic composition during the Neolithic period, revealing a key role for Late Neolithic cultures in shaping modern Central European genetic diversity.
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