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Categories: Anthropology: Early Humans, Ecology: Animals
Published Natural selection can slow evolution, maintain similarities across generations
(via sciencedaily.com) Original source New research suggests that natural selection, famous for rewarding advantageous differences in organisms, can also preserve similarities. The researchers worked with a plant called wild radish and its stamens, or pollen-producing parts, two of which are short and four are long. Roughly 55 million years ago, wild radish ancestors had stamens of equal length. The team selectively bred -- or artificially selected -- wild radish to reduce the difference in stamen length and return the plant to a more ancestral look. This shows that today's wild radish and, likely, its family members still have the requisite genetic variability to evolve, but natural selection is preserving its different stamen lengths.
Published Deforestation limits nesting habitat for cavity-nesting birds
(via sciencedaily.com) A new study of cavity-nesting birds in Ecuador shows the influence of deforestation on their habitat and reproductive success. Nest boxes could help.
Published Biodiversity protects against invasions of non-native tree species
(via sciencedaily.com) Researchers combined human and ecological factors to analyze the global scale of non-native tree species invasions. Human activity in hotspots of global trade, such as maritime ports, is linked to an increased likelihood of non-native tree species invasions. However, a high diversity of native tree species can help to curb the intensity of such invasions.
Published Vegetarian diet of corals explains age-old mystery dating back to Darwin
(via sciencedaily.com) Original source A new study has revealed why coral reefs can thrive in seemingly nutrient poor water, a phenomenon that has fascinated scientists since Charles Darwin.
Published Fire, disease threatening sanctuary plants for Australian wildlife
(via sciencedaily.com) Original source New research has revealed Australia's iconic grasstrees -- known as 'yaccas' -- play a critical role in protecting wildlife from deadly weather extremes, thereby ensuring their survival. But the grasses themselves are under threat due to back burning, clearing and disease.
Published Hundreds of Andean bird species at risk due to deforestation: New research shows how to protect them
(via sciencedaily.com) Original source Birds native to the tropical Andes are threatened by increasing agricultural development in the region. A new study combines a meta-analysis of papers on birds across the Andes with five years of fieldwork in Peru, revealing that open farmlands result in up to a 60% decline in the number of species in an area. The study documents how specific species are affected and provides tailored guidance for conservationists trying to protect them.
Published As city heat rises, bird diversity declines
(via sciencedaily.com) Original source A study done on 336 cities in China concludes that heat-retaining buildings and paved surfaces are directly related to a loss in bird diversity. It is likely that the patterns documented in this study are occurring in other large cities across the globe that have abundant asphalt, steel, and concrete with little green vegetation.
Published Detecting a vast diversity of rainforest animals by swabbing their DNA from leaves
(via sciencedaily.com) Researchers demonstrate that a vast multitude of birds and mammals can be detected by simply swabbing the DNA left behind by animals from leaves. They showcased the power of this approach in an ecosystem that hosts a ton of wildlife and where detecting animals has historically proven extremely challenging -- the tropical rainforest.
Published It all depends on the genetic diversity
(via sciencedaily.com) Original source New research shows that a single mutation that has immediate effects on plant fitness is maintained over the long term in natural plant populations, despite theories predict the contrary. The researchers located and identified the gene that regulates the amount of an active defense hormone. Mutants in this gene are susceptible to herbivore attack. However, they compensate for impaired defenses through robust genetic networks. When fewer herbivores attack, they even grow faster and produce more offspring.
Published Scientists zero in on timing, causes of ice age mammal extinctions in southern California
(via sciencedaily.com) Original source Radiocarbon dating on bones in the La Brea Tar Pits lead archaeologists to warn that history may be repeating itself.
Published Urban great tits have paler plumage than their forest-living relatives
(via sciencedaily.com) Original source A new study shows that urban great tits have paler plumage than their countryside counterparts. Since the yellow pigment of the breast feathers of great tits comes from the food they eat, the paler yellow plumage of urban birds indicates that the urban environment affects the entire food chain.
Published Pollutants are important to biodiversity's role in spread of wildlife diseases
(via sciencedaily.com) Conventional wisdom among ecologists holds that the more species there are inhabiting an ecosystem, the less vulnerable any one species will be to a threat like a parasite. A new study of tadpoles illustrates how overlapping biological and environmental factors can complicate how we value protecting diverse animal communities. The researchers found that environmental pollutants like road salt influence whether increased biodiversity helps or hinders disease outbreaks in wildlife, which can complicate how we value protecting diverse animal communities.
Published It's not just humans: City life is stressful for coyotes, too
(via sciencedaily.com) Original source Though cars are the biggest threat to coyotes taking up residence in U.S. cities, a new study suggests urban living poses a different kind of hazard to coyote health -- in the form of chronic stress. Researchers examined the concentration of the stress hormone cortisol in the hair of almost 100 coyotes living in the Chicago Metropolitan Area. Results showed that coyotes that lived in the most-developed areas had higher cortisol levels -- a proxy for chronic stress -- than animals living in suburban or natural areas.
Published Iceman Ötzi: Dark skin, bald head, Anatolian ancestry
(via sciencedaily.com) Original source A research team has used advanced sequencing technology to analyze Ötzi's genome to obtain a more accurate picture of the Iceman's appearance and genetic origins.
Published Key role of ice age cycles in early human interbreeding
(via sciencedaily.com) Original source Recent paleogenomic research revealed that interbreeding was common among early human species. However, little was known about when, where, and how often this hominin interbreeding took place. Using paleoanthropological evidence, genetic data, and supercomputer simulations of past climate, a team of international researchers has found that interglacial climates and corresponding shifts in vegetation created common habitats for Neanderthals and Denisovans, increasing their chances for interbreeding and gene flow in parts of Europe and central Asia.
Published Elephant ancestors´ teeth evolved in response to long term changes in diet and climate in Africa
(via sciencedaily.com) Original source A new study shows that the cheek teeth of proboscideans (elephants and their ancient relatives) evolved in response to dietary changes due to vegetation changes and climate change in East Africa during the last 26 million years.
Published A climate-orchestrated early human love story
(via sciencedaily.com) Original source A new study finds that past changes in atmospheric CO2 and corresponding shifts in climate and vegetation played a key role in determining when and where early human species interbred.
Published How a massive North Atlantic cooling event disrupted early human occupation in Europe
(via sciencedaily.com) Original source A new study finds that around 1.12 million years ago a massive cooling event in the North Atlantic and corresponding shifts in climate, vegetation and food resources disrupted early human occupation of Europe.
Published New insights into the origin of the Indo-European languages
(via sciencedaily.com) Original source An international team of linguists and geneticists has achieved a significant breakthrough in our understanding of the origins of Indo-European, a family of languages spoken by nearly half of the world's population.
Published Family trees from the European Neolithic
(via sciencedaily.com) Original source The Neolithic burial site of Gurgy 'les Noisats' in France revealed two unprecedentedly large family trees which allowed a Franco-German team to explore the social organization of the 6,700-year-old community. Based on multiple lines of evidence, the team describes a close kin group which practiced monogamy and female exogamy, and experienced generally stable times.