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Australian Flying Fox Die-offs
In the last two decades tens of thousands of Australian flying foxes have died during extreme heat events. Flying fox die-offs feature arguably among the most dramatic mass mortality events witnessed in nature, but they can be indicators of heat stress in more cryptic fauna where impacts are more difficult to assess. The die-offs are important additional threats to Australian flying-foxes and the ecosystem services they provide, and highlight the complex implications of climate change for behaviour, demography, and species survival. Impacts on species Two Australian flying fox species have reportedly been affected by extreme heat events: the grey-headed flying fox (''Pteropus poliocephalus'') and the black flying fox (''P. alecto''). Where mixed-species colonies are affected the black flying fox suffers substantially higher mortality than the grey-headed flying fox. However, summer temperatures are more extreme within the range of the grey-headed flying fox than within the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Image Of A Juvenile Grey-headed Flying Fox During An Extreme Temperature Event
A thermal column (or thermal) is a rising mass of buoyant air, a convective current in the atmosphere, that transfers heat energy vertically. Thermals are created by the uneven heating of Earth's surface from solar radiation, and are an example of convection, specifically atmospheric convection. Thermals on Earth The Sun warms the ground, which in turn warms the air directly above. The warm air near the surface expands, becoming less dense than the surrounding air. The lighter air rises and cools due to its expansion in the lower pressure at higher altitudes. It stops rising when it has cooled to the same temperature, thus density, as the surrounding air. Associated with a thermal is a downward flow surrounding the thermal column. The downward-moving exterior is caused by colder air being displaced at the top of the thermal. The size and strength of thermals are influenced by the properties of the lower atmosphere (the ''troposphere''). When the air is cold, bubbles of warm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flying Fox
''Pteropus'' (suborder Yinpterochiroptera) is a genus of megabats which are among the largest bats in the world. They are commonly known as fruit bats or flying foxes, among other colloquial names. They live in South Asia, Southeast Asia, Australia, East Africa, and some oceanic islands in the Indian and Pacific Oceans. There are at least 60 extant species in the genus. Flying foxes eat fruit and other plant matter, and occasionally consume insects as well. They locate resources with their keen sense of smell. Most, but not all, are nocturnal. They navigate with keen eyesight, as they cannot echolocate. They have long life spans and low reproductive outputs, with females of most species producing only one offspring per year. Their slow life history makes their populations vulnerable to threats such as overhunting, culling, and natural disasters. Six flying fox species have been made extinct in modern times by overhunting. Flying foxes are often persecuted for their real or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Sciences
Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary information encoded in genes, which can be transmitted to future generations. Another major theme is evolution, which explains the unity and diversity of life. Energy processing is also important to life as it allows organisms to move, grow, and reproduce. Finally, all organisms are able to regulate their own internal environments. Biologists are able to study life at multiple levels of organization, from the molecular biology of a cell to the anatomy and physiology of plants and animals, and evolution of populations.Based on definition from: Hence, there are multiple subdisciplines within biology, each defined by the nature of their research questions and the tools that they use. Like other scientists, biologists use the scientific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
