Evolution, genetics, animal behaviour, conservation
A wet Amazon may be more resilient to a drying climate than thought: Study
As a strategy to retain water, plants are thought to close their leaf pores in response to dry air, thereby also slowing their rate of photosynthesis. But a study that used machine learning to analyze satellite data found that in some of the wettest areas of the Amazon basin, photosynthesis rates actually increase in dry air.
The authors suggest that leaf ageing during the dry season may explain this unexpected result, but independent experts question the reliability of methods used to estima...
Conserve freshwater or land biodiversity? Why not both, new study asks
Freshwater ecosystems, such as rivers, lakes and streams, are home to 10% of all described species, but are often overlooked in conservation planning and their populations have shown rapid declines in recent decades.
An analysis of aquatic and terrestrial biodiversity in two regions of the Amazon Basin found that conservation planning aimed only at plants and animals on land tends not to benefit freshwater species, whereas taking a freshwater focus benefited species in both realms.
The widest...
Forest degradation outpaces deforestation in the Brazilian Amazon: Study
Brazilian Amazon deforestation rates have declined from, and stayed below, their 2003 peak, despite recent increases. However, this decline was offset by a trend of increased forest degradation, according to an analysis of 23 years of satellite data. By 2014, the rate of degradation overtook deforestation, driven by increases in logging and understory burning.
During the 1992-2014 study period, 337,427 square kilometers suffered a loss of vegetation, compared to 308,311 square kilometers comp...
Less than half of world’s humid tropical forests have high ecological integrity: Study
Over 93% of the Earth’s best-quality and least-disturbed tropical forests have no legal protection from destruction, according to a study published in Nature Ecology and Evolution.
Humid broadleaf tropical and subtropical forests cover just 14% of the Earth’s land surface, but support at least half of all species and offer key ecosystem services, making them crucial to meeting global climate and conservation targets.
As a result of human activities, 33% of the biome has already been deforeste...
Just half of major timber and pulp suppliers committed to zero deforestation: Report
The world’s 100 most significant timber and pulp companies score just 22.6%, on average, when assessed across 175 environmental, social, and governance indicators, according to the latest assessment by the Zoological Society of London using its Sustainability Policy Transparency Toolkit (SPOTT).
2020 is the first way-point towards the 2014 New York Declaration on Forests’ goal of eliminating natural forest loss by 2030, but 44% of companies still don’t have a robust commitment to halting the ...
Climate change could put tropical plant germination at risk: Study
Under a worst-case climate change scenario, more than 20% of plant species in the tropics may experience temperatures too high for their seeds to germinate by 2070, according to an analysis of seed germination data compiled by the UK’s Royal Botanic Gardens Kew.
Catastrophic Amazon tipping point less than 30 years away: study
The Amazon rainforest generates half its own rainfall, but deforestation threatens to disrupt this cycle, shifting large parts of this ancient forest to dry, savanna habitat. Passing such a “tipping point” would have disastrous knock-on effects for climate and weather patterns regionally and globally.
Bridges in the sky help slow lorises keep to the trees
The Indonesian island of Java has lost more than 90% of its original forest, confining tree-dwelling creatures to fragments of rainforest. That poses a threat to animals such as the critically endangered Javan slow loris (). This primate cannot leap, so it must travel on the ground to reach unconnected trees, exposing it to predators and parasites.
Brazil sugarcane growth can meet biofuel need and not drive deforestation: study
Sugarcane crop production in Brazil may need to expand by up to 5 million hectares by 2030 to meet a rising demand for ethanol biofuels, according to computer models that compared the impact of different economic, social, and policy scenarios on increased ethanol production.
The recent study found that sugarcane ethanol demand by 2030 would increase by between 17.5 and 34.4 million metric tonnes. This demand could be met without new deforestation by intensifying ranching practices and convert...
Amazon trees may absorb far less carbon than previously thought: study
The capacity of the Amazon rainforest to absorb carbon dioxide from the atmosphere is predicted to increase with climate change, but now computer modelling suggests that these increases may be far smaller than expected.
So far, global photosynthesis rates have risen in line with increases in atmospheric CO2 concentrations, but whether this pattern will hold true for the Amazon, one of the oldest ecosystems on Earth, is still unclear.
Depending on how key nutrient cycles are represented, resea...
Global Warming is Spoiling Sex
Across the natural world, the warming climate is leaving ladies without a mate, changing the rules of the playbook, putting partners out of sync and just generally spoiling the mood. Climate change may even be sterilising whole populations.
A shortage of males
Reptiles have a biological quirk that is putting them at risk of losing one sex entirely. This is because they use temperature to determine the sex of their offspring, rather than doing so genetically, like humans and other mammals. For...
Extraordinary fossil reveals sharks’ family roots
A strange-looking ancient fish that was closely related to modern sharks had an eel-like body and might have gulped small marine creatures whole.
Sharks belong to a group of fishes called elasmobranchs, which have skeletons of cartilage rather than bone. Because cartilage rarely fossilizes, scientists know little about this group’s early members.
Christian Klug at the University of Zurich in Switzerland and his colleagues found the nearly complete skeleton — including preserved cartilage and ...
Camera trap study reveals Amazon ocelot’s survival strategies
Ocelots living the Amazon basin prefer dense forest and avoid roads and human settlements, according to the largest ever camera trap study of this illusive wildcat, published in the journal Ecology and Evolution earlier this year.
The ocelot (Leopardus pardalis) is a medium-sized spotted cat found across the southwestern United States, central and South America.
Amazon REDD+ scheme side-steps land rights to reward small forest producers
To safeguard the almost 90 percent of its land still covered with forest, the small Brazilian state of Acre implemented a carbon credit scheme that assigns monetary value to stored carbon in the standing trees and rewards local “ecosystem service providers” for their role protecting it.
Acre’s System of Incentives for Environmental Services (SISA) rewards sustainable harvesting of rubber, nuts and other commodities from the forests. Crucially, it doesn’t make land tenure a prerequisite to qua...
Ocean acidification boosts algal growth but impairs ecological relationships
Shrimp fed on marine algae grown in acidic water do not undergo a sex change that is a characteristic part of their reproductive life-cycle, report Mirko Mutalipassi and colleagues at Stazione Zoologica Anton Dohrn in Italy in a study publishing June 26 in the open-access journal PLOS ONE.
The marine shrimp Hippolyte inermis lives in coastal meadows of the seagrass Posidonia oceanica and it has two breeding seasons a year, with some males born in spring developing rapidly and turning into fem...