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High genetic diversity and low differentiation reflect the ecological versatility of the African leopard

Large carnivores are generally sensitive to ecosystem changes because their specialized diet and position at the top of the trophic pyramid is associated with small population sizes. Accordingly, low genetic diversity at the whole-genome level has been reported for all big cat species, including the widely distributed leopard. However, all previous whole-genome analyses of leopards are based on th

Million-year-old DNA sheds light on the genomic history of mammoths

Temporal genomic data hold great potential for studying evolutionary processes such as speciation. However, sampling across speciation events would, in many cases, require genomic time series that stretch well back into the Early Pleistocene subepoch. Although theoretical models suggest that DNA should survive on this timescale1, the oldest genomic data recovered so far are from a horse specimen d

Genome-Based Sexing Provides Clues about Behavior and Social Structure in the Woolly Mammoth

While present-day taxa are valuable proxies for understanding the biology of extinct species, it is also crucial to examine physical remains in order to obtain a more comprehensive view of their behavior, social structure, and life histories [1, 2]. For example, information on demographic parameters such as age distribution and sex ratios in fossil assemblages can be used to accurately infer socio

Changes in variation at the MHC class II DQA locus during the final demise of the woolly mammoth

According to the nearly-neutral theory of evolution, the relative strengths of selection and drift shift in favour of drift at small population sizes. Numerous studies have analysed the effect of bottlenecks and small population sizes on genetic diversity in the MHC, which plays a central role in pathogen recognition and immune defense and is thus considered a model example for the study of adapti

Mitogenome evolution in the last surviving woolly mammoth population reveals neutral and functional consequences of small population size

The onset of the Holocene was associated with a global temperature increase, which led to a rise in sea levels and isolation of the last surviving population of woolly mammoths on Wrangel Island. Understanding what happened with the population's genetic diversity at the time of the isolation and during the ensuing 6000 years can help clarify the effects of bottlenecks and subsequent limited popula

A Skull Might Lie : Modeling Ancestral Ranges and Diet from Genes and Shape of Tree Squirrels

Tropical forests of Central and South America represent hotspots of biological diversity. Tree squirrels of the tribe Sciurini are an excellent model system for the study of tropical biodiversity as these squirrels disperse exceptional distances, and after colonizing the tropics of the Central and South America, they have diversified rapidly. Here, we compare signals from DNA sequences with morpho

Competitive mapping allows for the identification and exclusion of human DNA contamination in ancient faunal genomic datasets

BACKGROUND: After over a decade of developments in field collection, laboratory methods and advances in high-throughput sequencing, contamination remains a key issue in ancient DNA research. Currently, human and microbial contaminant DNA still impose challenges on cost-effective sequencing and accurate interpretation of ancient DNA data.RESULTS: Here we investigate whether human contaminating DNA

Homotopic Optimization for Autonomous Vehicle Maneuvering

Optimization of vehicle maneuvers using dynamic models in constrained spaces is challenging. Homotopic optimization, which has shown success for vehicle maneuvers with kinematic models, is studied in the case where the vehicle model is governed by dynamic equations considering road-tire interactions. This method involves a sequence of optimization problems that start with a large free space. By it

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In October 2023, Claudia Goldin, professor at Harvard University, was awarded the Nobel Prize in Economic Sciences, in recognition of her pioneering contributions to economics, particularly for her in-depth analysis of women’s place in the labor market. Goldin explored the evolution of women’s income and participation in the labor market over the long term, highlighting the causes of these changes

Investigating Characteristics and Opportunities for Rear-Wheel Steering

The potential of additional steering possibilities (like rear-wheel or all-wheel steering) is analyzed for critical situations to investigate possible safety improvements. For this purpose, a dynamic optimization problem is formulated to find the best possible maneuver. The optimization criterion is to maximize the entry speed into a constant radius 90°-curve. The optimization problem is solved fo

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The objective of this article is to study the links between the funding of primary education, access to education and economic growth in France in the 19th century. To do this, we use information on the funding allocated by the state, départements, local authorities, and households over the period 1820-1913. Our analysis consists of two stages. Firstly, we analyse the evolution of these different

The effect of equal versus expanding spacing practice on the deliberate learning of L2 collocations

Research comparing equal and expanding spacing schedules in relation to L2 single words is limited. Moreover, none of the existing studies has examined the learning of formulaic language. The current study aims to address this gap by investigating the impact of equal and expanding intervals on the long-term retention of L2 collocations in deliberate learning contexts. Eighty-three university learnResearch comparing equal and expanding spacing schedules in relation to L2 single words is limited. Moreover, none of the existing studies has examined the learning of formulaic language. The current study aims to address this gap by investigating the impact of equal and expanding intervals on the long-term retention of L2 collocations in deliberate learning contexts. Eighty-three university learn

The Paradox of Predictability Provides a Bridge Between Micro- and Macroevolution

The relationship between the evolutionary dynamics observed in contemporary populations (microevolution) and evolution on timescales of millions of years (macroevolution) has been a topic of considerable debate. Historically, this debate centers on inconsistencies between microevolutionary processes and macroevolutionary patterns. Here, we characterize a striking exception: emerging evidence indic

Structure-function analysis of time-resolved immunological phases in metabolic dysfunction-associated fatty liver disease (MASH) comparing the NIF mouse model to human MASH

Metabolic dysfunction-associated steatohepatitis (MASH) is a common but frequently unrecognized complication of obesity and type 2 diabetes. The association between these conditions is multifaceted and involves complex interactions between metabolic, inflammatory, and genetic factors. Here we assess the underlying structural and molecular processes focusing on the immunological phase of MASH in th

What is the prospect of a perennial grain revolution of agriculture?

Agriculture has been dominated by annual plants, such as all cereals and oilseeds, since the very beginning of civilization over 10,000 years ago. Annual plants are planted and uprooted every year which results in severe disturbance of the soil and disrupts ecosystem services. Science has shown that it is possible to domesticate completely new perennial grain crops, i.e. planted once and harvestedNon-technical summary:Agriculture has been dominated by annual plants, such as all cereals and oilseeds, since the very beginning of civilization over 10,000 years ago. Annual plants are planted and uprooted every year which results in severe disturbance of the soil and disrupts ecosystem services. Science has shown that it is possible to domesticate completely new perennial grain crops, i.e. plan