On May 9, the daily mean concentration of carbon dioxide in the atmosphere of Mauna Loa, Hawaii, surpassed 400 parts per million (ppm) for the first time since measurements began in 1958. Independent measurements made by both NOAA and the Scripps Institution of Oceanography have been approaching this level during the past week. It marks an important milestone because Mauna Loa, as the oldest continuous carbon dioxide measurement station in the world, is the primary global benchmark site for monitoring the increase of this potent heat-trapping gas.

The sacred lotus is a symbol of spiritual purity and longevity. Its seeds can survive up to 1,300 years, its petals and leaves repel grime and water, and its flowers generate heat to attract pollinators. Now researchers report that they have sequenced the lotus genome. Of all the plants sequenced so far — and there are dozens — sacred lotus bears the closest resemblance to the ancestor of all eudicots, a broad category of flowering plants that includes apple, cabbage, cactus, coffee and tobacco.

In contrast to traditional approaches using morphological characters to delimit species, five new lichen-forming fungal species were described from what was traditionally considered a single species using genetic data exclusively. The new species can be identified using DNA barcoding. This pioneering study marks an alternative approach for discovering species and will promote effective research through correct specimen identification in closely related species groups.

A recent research study has shed new light on the diet and food acquisition strategies of some the earliest human ancestors in Africa. Beginning around two million years ago, early stone tool-making humans, known scientifically as Oldowan hominin, started to exhibit a number of physiological and ecological adaptations that required greater daily energy expenditures, including an increase in brain and body size, heavier investment in their offspring and significant home-range expansion. Demonstrating how these early humans acquired the extra energy they needed to sustain these shifts has been the subject of much debate among researchers.

American kestrels, small colorful falcons often seen perched along roadways, are abundant in urban and agricultural areas. Shorter grass makes insects, snakes, mice and other prey more visible, and signposts, fences and telephone poles provide excellent perches. However a new study shows that even species considered “tolerant” of human activity may be adversely impacted by human disturbance; Kestrels nesting in close proximity to roads and developed areas had elevated stress hormones and high rates of nest abandonment. The apparently favorable location, then, becomes an ecological trap.

The large-scale expansion of agriculture in the Amazon through deforestation will be a no-win scenario, according to a new study. The study shows that deforestation will not only reduce the capacity of the Amazon’s natural carbon sink, but will also inflict climate feedbacks that will decrease the productivity of pasture and soybeans.

The so-called Elephant’s Tomb in the Roman necropolis of Carmona (Seville, Spain) was not always used for burials. The original structure of the building and a window through which the sun shines directly in the equinoxes suggest that it was a temple of Mithraism, an unofficial religion in the Roman Empire. The position of Taurus and Scorpio during the equinoxes gives force to the theory.

Ancient DNA analyses of skeletal remains of plague victims from the 6th century AD provide information about the phylogeny and the place of origin of this pandemic.

A novel gene associated with canine atopic dermatitis has been identified. The gene encodes a protein called plakophilin 2, which is crucial for the formation and proper functioning of the skin structure, suggesting an aberrant skin barrier as a potential risk factor for atopic dermatitis.