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Life history traits determine fitness and hence the ability of populations and species to survive through adverse conditions. Therefore, identifying temporal changes in life history traits over large timescales is necessary to understand and predict the effect of current global change on wild populations. In this study, we compare life history traits between Palaeolithic and present-day vertebrates, analysing the number of winters spent in the river and at sea by North Iberian salmonids ( Salmo salar and Salmo trutta) from two separate time frames: the Upper Palaeolithic, based on archaeological remains, and the present day, based on sport catches. The river stage did not change significantly, but the marine period has been shortened in modern anadromous specimens, accordingly shortening mean generation time. Population growth rates have been estimated through Bayesian analyses of the mitochondrial DNA control region of modern specimens for the two Salmo species using two different mutation rates (1% and 3.6%). Coincidence of coalescent N e estimates with independent N e calculated from catches suggests that the 3.6% mutation rate fits better the evolution of the studied populations. Population growth rate declines would have occurred in the last millennium and could be explained by a combination of climatic events and anthropogenic activities. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) is a neurodegenerative disorder, clinically defined by a progressive loss of memory and other cognitive and functional abilities. One of the most studied phases in the prognosis of AD is the Mild cognitive impairment (MCI) since it entails a higher risk of developing this type of dementia. The majority longitudinal studies from MCI to AD utilize both a reduce number of potential prediction markers and a shorten length of follow‐up. Therefore, the present study was aimed at determining which combination of demographic, genetic, cognitive, neurophysiological (i.e. magnetoencephalography, MEG), and neuroanatomical (i.e. magnetic resonance imaging (MRI) volumetry) factors may predict differences in time to progression from MCI to AD during an extended follow‐up. Method: To this end, a sample of 121 MCIs was followed‐up during a 5‐years period. According to their clinical outcome, MCIs were divided into two subgroups: (i) the "progressive" MCI (pMCI; n= 46); and (ii) the "stable" MCI group (sMCI; n= 75). Kaplan‐Meier survival analyses were applied to explore each variable's relationship with the progression to AD. Once potential predictors were detected, Cox regression analyses were utilized to calculate a parsimonious model that may allow the estimation of differences in time to progression. Result: Results indicated that the final model included three variables (in order of relevance): Left parahippocampal volume (corrected by intracranial volume, LP_ ICV), Delayed recall (DR), and Left Inferior Occipital lobe individual alpha peak frequency (LIOL_IAF). Those MCIs with LP_ ICV volume, DR score and LIOL_IAPF value lower than the defined cutoff had 6‐times, 5.5‐times and 3‐times higher risk of progression to AD, respectively. Besides, when the categories of the three variables were "unfavourable" (i.e. values below the cutoff), a 100% of cases progressed to AD at the end of follow‐ up, while a combination of "favourable" categories yielded a 94.7% of stable cases at the end of follow‐up. Conclusion: Our results highlighted the relevance of neurophysiological markers as predictors of conversion, and the importance of multivariate models that combine markers of different nature to predict time to progression from MCI to dementia. [ABSTRACT FROM AUTHOR]