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Aim Spatial synchrony in plankton is imperfectly understood yet may have far-reaching implications, for example for carbon export to the deep ocean. Several techniques have been used to describe patterns of spatial synchrony, from correlation coefficients to spectral methods. Some studies have used temporally extensive data sets to identify causes of synchrony. This study instead uses the exceptional spatial extent provided by remotely sensed data to describe, for the first time as far as we know, geographical patterns of synchrony in marine phytoplankton. We use these patterns to illuminate drivers of synchrony and of its geography. Location The oceans. Time period 2003–2015. Major taxon Chlorophyll a-containing phytoplankton. Methods Synchrony in chlorophyll a concentrations is mapped globally. Spatial statistics and model selection are used to illuminate main statistical determinants of synchrony and of geographical patterns in synchrony. Results The first main result is that there is a pronounced and previously unmapped geography of synchrony for phytoplankton. For instance, synchrony was highest in the open ocean, specifically in gyres, and lowest in coastal regions. Spatial modelling provided the second main result that synchrony in sea surface temperature (SST) was a major statistical determinant of chlorophyll synchrony in both the Pacific and Atlantic Oceans, indicating a strong Moran effect, although possibly an indirect and/or complex one. In the Pacific Ocean, this effect depended on the time-scales on which synchrony was assessed, providing our third result, which is that synchrony of phytoplankton and its geography can be time-scale specific. Synchrony of surface solar irradiance was not associated with synchrony of chlorophyll. Main conclusions To our knowledge, this study is the first to map geography of synchrony in marine plankton. We showed that this geography is pronounced. Geographical patterns illuminated determinants of synchrony. The geography of synchrony is a major phenomenon that has been little explored.

Aim: Previous work demonstrated a pronounced geography of synchrony for marine phytoplankton, and used that geography to infer statistical environmental determinants of synchrony. He re we determine if terrestrial vegetation (measured by the Enhanced Vegetation Index, EVI) also shows a geography of synchrony, and we infer determinants of EVI synchrony. As vegetation is the basis of the terrestrial food web, changes in spatio - temporal v egetation dynamics may have major consequences. Location: The land. Time period: 2001 - 2014 . Major taxa: Plants . Methods: Synchrony in terrestrial vegetation is mapped globally. Spatial statistics and model selection are used to identify main statistical determinants of synchrony and of geographic patterns in synchrony. Results: The first main result is that there is a pronounced and previously unrecognized geography of synchrony for terrestrial vegetation. Some areas such as the Sahara and Southern Africa exhibited nearly perfect synchrony, whereas other areas such as the Pacific coast of South America showed very little synchrony. Spatial modeling provided the second main result that synchrony in temperature and precipitation were major determinants of sy nchrony in EVI, supporting the presences of dual global Moran effects. These effects depended on the timescales on which 3 synchrony was assessed, providing our third main result: synchrony of EVI and its geography are timescale specific. Main conclusions: T o our knowledge, this study is the first to document the geography of synchrony in terrestrial vegetation . W e showed geographic variation in synchrony is pronounced. We used geographic patterns to identify determinants of synchrony. This study is one of ve ry few studies to demonstrate two separate synchronous environmental variables driving synchrony simultaneously. The geography of synchrony is apparently a major phenomenon that has been little explored.

During the 1980s the North Sea plankton community underwent a well-documented ecosystem regime shift, including both spatial changes (northward species range shifts) and temporal changes (increases in the total abundances of warmer-water species). This regime shift has been attributed to climate change. Plankton provide a link between climate and higher-trophic-level organisms, which can forage on large spatial and temporal scales. It is therefore important to understand not only whether climate change affects purely spatial or temporal aspects of plankton dynamics, but also whether it affects spatio-temporal aspects such as metapopulation synchrony. If plankton synchrony is altered, higher-trophic-level feeding patterns may be modified. A second motivation for investigating changes in synchrony is that the possibility of such alterations has been examined for few organisms, in spite of the fact that synchrony is ubiquitous and of major importance in ecology. This study uses correlation coefficients and spectral analysis to investigate whether synchrony changed between the periods 1959-1980 and 1989-2010. Twenty-three plankton taxa, sea surface temperature (SST), and wind speed were examined. Results revealed that synchrony in SST and plankton was altered. Changes were idiosyncratic, and were not explained by changes in abundance. Changes in the synchrony of Calanus helgolandicus and Para-pseudocalanus spp appeared to be driven by changes in SST synchrony. This study is one of few to document alterations of synchrony and climate-change impacts on synchrony. We discuss why climate-change impacts on synchrony may well be more common and consequential than previously recognized.

The reconstruction of invasion history is the goal or foundation of many investigations of biological invasions. This study applies DNA profiling to investigate the sources and vectors of new propagules, to detect illegal human-mediated translocations and to improve the management of invasions, by identifying invasion pathways that can be targeted for more stringent control. We use the European invasion of the American Eastern grey squirrel as a focal example. Many human-mediated translocations of this species have occurred in Europe since the 19th century. We built a genotype database of 1421 individuals from 59 locations across Europe and one in the USA, with each individual genotyped at 12 highly polymorphic microsatellites. DNA from newly detected populations and individuals of unknown sources were compared with this database. Our results indicated illegal human-mediated translocations in Aberdeen, the Isle of Skye and Northumberland in the UK, and revealed precise details of illegal squirrel trade in Italy. We recommend that multi-locus genotype databases be set up for all major invasive species considered attractive or ornamental, as these are often subject to illegal translocations through human actions such as the pet trade.