01 Feb Watch Plants Light Up When They Get Attacked

Plants have no eyes, no ears, no mouth and no hands. They do not have a brain or a nervous system. Muscles? Forget them. They’re stuck where they started, soaking up the sun and sucking up nutrients from the soil. And yet, when something comes around to eat them, they sense it.

And they fight back.

Sourced through Scoop.it from: www.nytimes.com

29 Jan Underwater caves – hunting for new forms of life

Cave-inhabiting animals are often categorized as troglobites (cave-limited species), troglophiles (species that can live their entire lives in caves, but also occur in other environments), trogloxenes (species that use caves, but cannot complete their life cycle fully in caves) and accidentals (animals not in one of the previous categories). Some scientists use a separate terminology for aquatic forms (e.g., stygobites, stygophiles, and stygoxenes).

Sourced through Scoop.it from: theconversation.com

29 Jan Planetary collision that formed the moon made life possible on Earth

Most of Earth’s essential elements for life—including most of the carbon and nitrogen in you—probably came from another planet.

Earth’s status as the only life-sustaining planet is a result of the timing and delivery mechanism of carbon (C), nitrogen (N), sulfur (S), and hydrogen (H). On the basis of their isotopic signatures, terrestrial volatiles are thought to have derived from carbonaceous chondrites, while the isotopic compositions of nonvolatile major and trace elements suggest that enstatite chondrite–like materials are the primary building blocks of Earth. However, the C/N ratio of the bulk silicate Earth (BSE) is superchondritic, which rules out volatile delivery by a chondritic late veneer. In addition, if delivered during the main phase of Earth’s accretion, then, owing to the greater siderophile (metal loving) nature of C relative to N, core formation should have left behind a subchondritic C/N ratio in the BSE.

Sourced through Scoop.it from: phys.org

22 Jan New Caledonian crows infer the weight of objects from observing their movements in a breeze

Humans use a variety of cues to infer an object’s weight, including how easily objects can be moved. For example, if we observe an object being blown down the street by the wind, we can infer that it is light. A team of scientists tested now whether New Caledonian crows make this type of inference. After training that only one type of object (either light or heavy) was rewarded when dropped into a food dispenser, birds observed pairs of novel objects (one light and one heavy) suspended from strings in front of an electric fan. The fan was either on—creating a breeze which buffeted the light, but not the heavy, object—or off, leaving both objects stationary. In subsequent test trials, birds could drop one, or both, of the novel objects into the food dispenser. Despite having no opportunity to handle these objects prior to testing, birds touched the correct object (light or heavy) first in 73% of experimental trials, and were at chance in control trials. These results suggest that birds used pre-existing knowledge about the behavior exhibited by differently weighted objects in the wind to infer their weight, using this information to guide their choices.

Sourced through Scoop.it from: royalsocietypublishing.org