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The author revists Selma to Montgomery National Historic Trail, created by Congress to commemorate the historic march of 1965. The only African American site in the entire National Trail System, Selma to Montgomery represents the historical tension between the ideals of American democracy, where all citizens have equal protection and equal rights by law, and the reality of the fight waged by Black voters against discrimination in America. Further, the trail represents the struggle to preserve the history and memory of civil rights sites of conflict as a part of the nation’s historical landscape. Finally, the trail represents the symbolic battle, in real time, of the voting rights movement (which some characterize as “a relic of the past”) in the face of ongoing tangible assaults on voting rights in the 21st century.

Background: Movement behaviour is fundamental to the ecology of animals and their interactions with other organisms, and as such contributes to ecosystem dynamics. Waterfowl are key players in ecological processes in wetlands and surrounding habitats through predator-prey interactions and their transportation of nutrients and other organisms. Understanding the drivers of their movement behaviour is crucial to predict how environmental changes affect their role in ecosystem functioning. Mallards (Anas platyrhynchos) are the most abundant duck species worldwide and important dispersers of aquatic invertebrates, plants and pathogens like avian influenza viruses. By GPS tracking of 97 mallards in four landscape types along a gradient of wetland availability, we identified patterns in their daily movement behaviour and quantified potential effects of weather conditions and water availability on the spatial scale of their movements. Results: We demonstrate that mallard movement patterns were highly predictable, with regular commuting flights at dusk and dawn between a fixed day roost and one or several fixed nocturnal foraging sites, linked strongly to surface water. Wind and precipitation hardly affected movement, but flight distances and home range sizes increased when temperatures dropped towards zero. Flight distances and home range sizes increased exponentially with decreasing availability of freshwater habitat. Total shoreline length and the number of water bodies in the landscape surrounding the roost were the best predictors of the spatial scale of daily mallard movements. Conclusions: Our results show how mallards may flexibly adjust the spatial scale of their movements to wetland availability in the landscape. This implies that mallards moving between discrete habitat patches continue to preserve biotic connectivity in increasingly fragmented landscapes. The high predictability of mallard movement behaviour in relation to landscape features makes them reliabl

Movement behaviour is fundamental to the ecology of animals and their interactions with other organisms, and as such contributes to ecosystem dynamics. Waterfowl are key players in ecological processes in wetlands and surrounding habitats through predator-prey interactions and their transportation of nutrients and other organisms. Understanding the drivers of their movement behaviour is crucial to predict how environmental changes affect their role in ecosystem functioning. Mallards (Anas platyrhynchos) are the most abundant duck species worldwide and important dispersers of aquatic invertebrates, plants and pathogens like avian influenza viruses. By GPS tracking of 97 mallards in four landscape types along a gradient of wetland availability, we identified patterns in their daily movement behaviour and quantified potential effects of weather conditions and water availability on the spatial scale of their movements.

Movement behaviour is fundamental to the ecology of animals and their interactions with other organisms, and as such contributes to ecosystem dynamics. Waterfowl are key players in ecological processes in wetlands and surrounding habitats through predator-prey interactions and their transportation of nutrients and other organisms. Understanding the drivers of their movement behaviour is crucial to predict how environmental changes affect their role in ecosystem functioning. Mallards (Anas platyrhynchos) are the most abundant duck species worldwide and important dispersers of aquatic invertebrates, plants and pathogens like avian influenza viruses. By GPS tracking of 97 mallards in four landscape types along a gradient of wetland availability, we identified patterns in their daily movement behaviour and quantified potential effects of weather conditions and water availability on the spatial scale of their movements.

In sequence-controlled polymers, repeat units of different chemical composition are arranged in a well-defined order. Due to its living characteristics and functional group tolerance, ruthenium-mediated ring-opening metathesis polymerization (ROMP) is a powerful strategy for sequence control. Catalysts for ROMP can be tuned to achieve polymers with highly controlled sequences, thereby encoding structural information in the structure of the catalyst itself. The study of sequence-cotrolled polymerization offers both mechanistic insights and routes to new materials with precise structure–property relationships. This chapter will review design strategies for ruthenium-mediated sequence-controlled ROMP. Structural control in terms of cis/trans-selectivity and tacticity will first be discussed to illustrate the key principles of catalyst design. This framework will then be extended to sequence control for alternating copolymerization, with the goal of motivating continued progress in this area.