Search Results (8)

This article critically considers sample multigenerational oral traditions of Numic-speaking communities known as the Nüümü (Northern Paiute), Nuwu (Southern Paiute), and Newe (Western Shoshone), written down over the last 151 years. Utilizing the GOAT! phenomenological method to compare the onto-epistemologies of Numic peoples with a wide range of data from (G)eology, (O)ral traditions, (A)rchaeology and (A)nthropology, and (T)raditional knowledge, the author analyzed 824 multigenerational ancestral teachings. These descriptions encode multigenerational memories of potential geological, climatic, and ecological observations and interpretations of multiple locations and earth processes throughout the Numic Aboriginal homelands within California and the Great Basin. Through this layered and comparative analysis, the author identified potential convergences of oral traditions, ethnography, ethnohistory, rock art, and geological processes in the regions of California, the Great Basin, and the Colorado Plateau, indicative of large-scale earth changes, cognized by Numic Indigenous communities as earth birthing events, occurring during the Late Pleistocene/Early Holocene to Middle and Late Holocene, including the Late Dry Period, Medieval Climatic Anomaly, and Little Ice Age. Full article

In this work, we explore the way in which rock art mediates social memory. Our study case is based on the rock art sequence established for Los Toldos archaeological locality, Argentina, which begins in the Pleistocene/Holocene transition and extends to the Late Holocene. The analysis focuses on superimpositions, with an emphasis on the human attitudes towards previous images. Despite changes detected along the sequence, Los Toldos manifests a strong emphasis on recalling the past, which is evidenced by the superimposition, replication, maintenance and recycling of motifs. These behaviors show a multi-generational dialogue that kept an ancestral memory alive but also recreated it through grouping images from different times for telling stories. This study places an emphasis on the users/consumers of rock art rather than on its makers. This focus narrows the gap between the archaeological record and the ethnographic sources by claiming that the Tehuelche people were engaged with rock art even though they did not make it. Full article

Continuous exposure to stress contributes to species diversity and drives microevolutionary processes. It is still unclear, however, whether epigenetic changes, in the form of epimutations such as, for example, differential DNA methylation, are the pre-requisite to speciation events. We hypothesized that continuous stress exposure would increase epigenetic diversity to a higher extent than genetic diversity. In this work, we have analyzed the effect of 25 consecutive generations of UV-C-stress exposure on the Arabidopsis thaliana genome and epigenome. We found no evidence of increased tolerance to UV-C in the progeny of UV-C-stressed plants (F25UV) as compared to the progeny of control plants (F25C). Genetic analysis showed an increased number of single nucleotide polymorphisms (SNPs) and deletions in F25UV plants. Most common SNPs were mutations in cytosines, C to T, C to A, and C to G. Analysis of cytosine methylation showed a significant increase in the percentage of methylated cytosines at CG context in F25UV as compared to F25C or F2C (parental control). The most significant differences between F25UV and either control group were observed in CHG and CHH contexts; the number of hypomethylated cytosines at CHH contexts was over 10 times higher in the F25UC group. F25UV plants clustered separately from other groups in both genomic and epigenomic analyses. GO term analysis of differentially methylated genes revealed enrichments in “DNA or RNA metabolism”, “response to stress”, “response to biotic and abiotic stimulus”, and “signal transduction”. Our work thus demonstrates that continuous exposure to UV-C increases genomic and epigenomic diversity in the progeny, with epigenetic changes occurring in many stress-responsive pathways. Full article

Persister cells (PCs), a subpopulation occurring within normal cells, exhibit a transient tolerance to antibiotics because of their dormant state. PCs are categorized into two types: type I PCs, which emerge during the stationary phase, and type II PCs, which emerge during the logarithmic phase. Using the conventional colony-forming method, we previously demonstrated that type I PCs of Escherichia coli form more frequently in air–solid biofilm culture than in liquid culture. In the current study, we modified a cell filamentation method as a more efficient and rapid alternative for quantifying PCs. This modified method yielded results consistent with those of the conventional method with 10³–10⁴ times higher sensitivity and less detection time, within several hours, and further revealed the existence of multiple levels of type I PCs, including a substantial number of deeply dormant cells. This study also discovered a potential epigenetic memory mechanism, spanning several generations (four or six cell divisions), which influences type II PC formation based on prior biofilm experience in E. coli. Full article

Plants are continuously exposed to various environmental stresses. Because they can not escape stress, they have to develop mechanisms of remembering stress exposures somatically and passing it to the progeny. We studied the Arabidopsis thaliana ecotype Columbia plants exposed to cold stress for 25 continuous generations. Our study revealed that multigenerational exposure to cold stress resulted in the changes in the genome and epigenome (DNA methylation) across generations. Main changes in the progeny were due to the high frequency of genetic mutations rather than epigenetic changes; the difference was primarily in single nucleotide substitutions and deletions. The progeny of cold-stressed plants exhibited the higher rate of missense non-synonymous mutations as compared to the progeny of control plants. At the same time, epigenetic changes were more common in the CHG (C = cytosine, H = cytosine, adenine or thymine, G = guanine) and CHH contexts and favored hypomethylation. There was an increase in the frequency of C to T (thymine) transitions at the CHH positions in the progeny of cold stressed plants; because this type of mutations is often due to the deamination of the methylated cytosines, it can be hypothesized that environment-induced changes in methylation contribute to mutagenesis and may be to microevolution processes and that RNA-dependent DNA methylation plays a crucial role. Our work supports the existence of heritable stress response in plants and demonstrates that genetic changes prevail. Full article

After providing an introduction to German language family narratives of the past forty years and discussing the relevance of Michael Rothberg’s notion of the “Implicated Subject” for the study of these narratives, this article presents a detailed analysis of Susanne Fritz’s German-Polish family history Wie kommt der Krieg ins Kind (How does the war get into the child, 2018). Exemplifying the archival turn in postmemorial writings, the book draws on multiple sources and makes a compelling case for a broader public acknowledgment of the incarceration of German civilians (including the author’s mother) in post-war Polish labor camps, to this day a little-known aspect of German wartime suffering. The article examines on the one hand the intertwined nature of the mother’s wartime memories and the daughter’s postmemories and, on the other, questions of “implication” at the historical and the textual level (i.e., regarding the ancestors’ involvement in Nazi Germany and regarding the narrator’s positioning vis-à-vis her family history). The central challenge the narrative grapples with is how the suffering of Germans can be addressed within a larger perpetrator heritage. In its critical examination of archival materials and its multi-faceted examination of implication, the book makes a significant contribution to the collective memory of the (post-) war period as well as to the academic study of memory. Full article

Nitrogen (N) deficiency is one of the major stresses that crops are exposed to. It is plausible to suppose that a stress condition can induce a memory in plants that might prime the following generations. Here, an experimental setup that considered four successive generations of N-sufficient and N-limited Arabidopsis was used to evaluate the existence of a transgenerational memory. The results demonstrated that the ability to take up high amounts of nitrate is induced more quickly as a result of multigenerational stress exposure. This behavior was paralleled by changes in the expression of nitrate responsive genes. RNAseq analyses revealed the enduring modulation of genes in downstream generations, despite the lack of stress stimulus in these plants. The modulation of signaling and transcription factors, such as NIGTs, NFYA and CIPK23 might indicate that there is a complex network operating to maintain the expression of N-responsive genes, such as NRT2.1, NIA1 and NIR. This behavior indicates a rapid acclimation of plants to changes in N availability. Indeed, when fourth generation plants were exposed to N limitation, they showed a rapid induction of N-deficiency responses. This suggests the possible involvement of a transgenerational memory in Arabidopsis that allows plants to adapt efficiently to the environment and this gives an edge to the next generation that presumably will grow in similar stressful conditions. Full article

The Pacific oyster, Crassostrea gigas, is becoming a valuable model for investigating antiviral defense in the Lophotrochozoa superphylum. In the past five years, improvements to laboratory-based experimental infection protocols using Ostreid herpesvirus I (OsHV-1) from naturally infected C. gigas combined with next-generation sequencing techniques has revealed that oysters have a complex antiviral response involving the activation of all major innate immune pathways. Experimental evidence indicates C. gigas utilizes an interferon-like response to limit OsHV-1 replication and spread. Oysters injected with a viral mimic (polyI:C) develop resistance to OsHV-1. Improved survival following polyI:C injection was found later in life (within-generational immune priming) and in the next generation (multi-generational immune priming). These studies indicate that the oyster’s antiviral defense system exhibits a form of innate immune-memory. An important priority is to identify the molecular mechanisms responsible for this phenomenon. This knowledge will motivate the development of practical and cost-effective treatments for improving oyster health in aquaculture. Full article