Category: Life on Earth

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Life on Earth Astronomy Evolution People

Humans walking on two legs because of exploding stars, new study says

Evolution of bipedalism (walking on two legs)
As the forests shrank, it would have become harder and more time-consuming for individuals to find food. One theory, suggested by anthropologist C. Owen Lovejoy of Kent State University, says "a mutually beneficial arrangement evolved: males gathered food for females and their young and in return females mated exclusively with their providers. To be successful providers, males needed their arms and hands-free to carry food, and thus bipedalism evolved." Another theory considers the efficiency of upright walking. In the 1980s, Peter Rodman and Henry McHenry, both at the University of California, Davis, suggested that "...as forests shrank, hominid ancestors found themselves descending from the trees to walk across stretches of grassland that separated forest patches". The most energetically efficient way to walk on the ground was on two legs, Rodman and McHenry argued.

Walking on two legs is an evolutionary leap that led humans to conquer the world. But, why humans are walking on two legs? It’s still unclear. Now, according to a new study published in the University of Chicago’s Journal of Geology, the reason might be exploding stars a few million years ago.

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Life on Earth Animals Climate Global Warming Insects Plants

UN report warns one million species at risk of extinction

Proboscis monkey
The proboscis monkey (Nasalis larvatus) or long-nosed monkey is a reddish-brown arboreal Old World monkey with an unusually large nose. It is endemic to the southeast Asian island of Borneo and known as "the bekantan" in Indonesia. The proboscis monkey is a large species, being one of the largest monkey species native to Asia. Only the Tibetan macaque and a few of the gray langurs can rival its size. Sexual dimorphism is pronounced in the species. Males have a head-body length of 66 to 76.2 cm (26.0 to 30.0 in) and typically weigh 16 to 22.5 kg (35 to 50 lb), with a maximum known weight of 30 kg (66 lb). Females measure 53.3 to 62 cm (21.0 to 24.4 in) in head-and-body length and weigh 7 to 12 kg (15 to 26 lb), with a maximum known mass of 15 kg (33 lb). They generally live in groups composed of one adult male, some adult females and their offspring. All-male groups may also exist. Some individuals are solitary, mostly males. The proboscis monkey is assessed as endangered in the IUCN Red List of Threatened Species and listed in Appendix I of CITES. Its total population has decreased by more than 50% in the past 36-40 years to 2008 due to ongoing habitat loss because of logging and oil palm plantations, and hunting in some areas due to the species being treated as a delicacy, as well as its use in traditional Chinese medicine. Text Source: Wikipedia Photo: PXHere

We, humans, are destroying the Earth’s wilderness, very fast. Actually, we are the main (and probably the only) cause of the sixth major extinction event in the history of our planet. Now, a recent UN report says at least one million species (animals, plants, and insects) are at the risk of extinction. There will be serious consequences for life on Earth, and also for human beings.

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Astronomy Evolution Life on Earth Planet Earth Solar System

Two neutron stars collided near the solar system 4.6 billion years ago

Two Neutron Stars Collide - explosion
The merger of two neutron stars is an extremely powerful event. Gravitational waves (pale arcs) bleed away orbital energy, causing the stars to move closer together and merge. As the stars collide, some of the debris blasts away in particle jets moving at nearly the speed of light, producing a brief burst of gamma rays (magenta). In addition to the ultra-fast jets powering the gamma-rays, the merger also generates slower moving debris. An outflow driven by accretion onto the merger remnant emits rapidly fading ultraviolet light (violet). A dense cloud of hot debris stripped from the neutron stars just before the collision produces visible and infrared light (blue-white through red). The UV, optical and near-infrared glow is collectively referred to as a kilonova. Later, once the remnants of the jet directed toward us had expanded into our line of sight, X-rays (blue) were detected.

According to a new study published in the May 2, 2019 issue of Nature, 4.6 billion years ago, two neutron stars collided near the early Solar System (actually about 1000 light-years from the gas cloud that eventually formed the Solar System). This violent collision has created heavy elements like silver, gold, platinum, cesium, and uranium. The study says 0.3% of the Earth’s heaviest elements have been created by this event.

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Earth from Space Climate Environment Global Warming Life on Earth Plants Space Exploration

GEDI: NASA’s Laser Mission to Measure Trees

GEDI is NASA's Laser Mission to Measure Trees
GEDI is NASA's Laser Mission to Measure Trees. It is attached to the International Space Station (ISS) and weighs about a thousand pounds (454 kg) and looks like a refrigerator. It has a telescope of about 80 cm (31 in) in diameter. It has three laser ports and shoots out four laser beams that are then dithered, really quickly, in between shots. It makes one laser look like two. So GEDI is a laser altimeter. We have lasers that emit pulses of light, they travel down to the Earth, they get reflected from the Earth, and then we receive the reflection. We time how long it gets there, which allows us to measure the range to the surface. When the pulse of light hits the surface, it gets distorted and stretched out by any structure that is there.

NASA’s Global Ecosystem Dynamics Investigation (GEDI) on the International Space Station (ISS) beams laser light down to Earth to reveal the height and density of trees and vegetation.

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Environment Animals Evolution Life on Earth

It would take at least 3 million years for Earth to recover from the 6th mass extinction

Elephants in Okavango Delta, Botswana
Elephants in the Okavango Delta. The area is one of the best places to see animals and birds in Africa. The area supports large concentrations of animals on both a permanent and seasonal basis. A myriad of species are found within the delta including African Bush Elephant, African Buffalo, Hippopotamus, Lechwe, Topi, Blue Wildebeest, Giraffe, Nile crocodile, Lion, Cheetah, Leopard, Brown Hyena, Spotted Hyena, Greater Kudu, Sable Antelope, Black Rhinoceros, White Rhinoceros, Plains Zebra, Warthog and Chacma Baboon. Notably the endangered African Wild Dog still survives within the Okavango Delta and exhibits one of the richest pack densities in Africa. In addition to these large animals the Okavango Delta also supports over 400 species of birds and 71 recorded species of fish including Tigerfish, Tilapia and Catfish. Thanks to this wide variety of wildlife, the delta is now a popular tourist attraction.

Even if we stop destroying Earth’s wilderness today, it would take 3 to 5 million years for Earth to recover from the 6th mass extinction, scientists warn.

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Animals Evolution Life on Earth Oceans

Blue whale facts: How big is the blue whale?

Blue whale and diver
Blue whale size compared to an average human. The blue whale (Balaenoptera musculus) is a marine mammal belonging to the baleen whales (Mysticeti). At 30 metres (98 ft) in length and up to 173 tonnes (191 short tons) in weight, it is the largest extant animal and is the heaviest known to have existed. Photo: dkfindout.com

The blue whale (scientific name: Balaenoptera musculus) is a marine mammal belonging to the baleen whales (Mysticeti). Up to 31 meters (102 feet) in length and 190 tonnes (210 short tons) in weight, it is the largest extant animal and also is the heaviest known to have existed. But it’s hard to conceptualize how big these wonderful animals really are. To put things into perspective, the Facts in Motion channel prepared a video titled “Blue Whales Are Way Bigger Than You Think”. The video also explains the evolutionary reasons behind how and why blue whales get that large.

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Global Warming Climate Life on Earth Prehistoric

We are pumping 10 times more carbon into the atmosphere than when there were palm trees in the Arctic

Palm trees during the sunset
Palm trees during the sunset. Image source: Pxhere Around 55.5 million years ago, there was a time period with more than 5°C - 8 °C warmer global average temperature than today, which named "Paleocene-Eocene Thermal Maximum" (PETM). As a result, there were crocodiles and even crocodiles in the Arctic and the region was completely ice-free. Now, a new study suggests that if we keep burning fossil fuels at the current rate, the Earth will be again 8 degrees warmer within the next few hundred years. We're going to face another PETM-like event soon.

Around 55.5 million years ago, there was a time period with more than 5°C – 8 °C warmer global average temperature than today, which named “Paleocene-Eocene Thermal Maximum” (PETM). As a result, there were crocodiles and even crocodiles in the Arctic and the region was completely ice-free. Now, a new study suggests that if we keep burning fossil fuels at the current rate, the Earth will be again 8 degrees warmer within the next few hundred years. We are pumping 10 times more carbon into the atmosphere than when there were palm trees in the Arctic. We’re going to face another PETM-like event soon.

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Evolution Life on Earth Physics

Is Evolution “just a theory”?

Timeline evolution of life (cropped)
Yes, the Theory of Evolution is a theory, but guess what? When scientists use the word theory, it has a different meaning to normal everyday use. A scientific theory is an explanation of some aspect of the natural world that has been substantiated through repeated experiments or testing. In science, a theory is not a guess, not a hunch. It’s a well-substantiated, well-supported, well-documented explanation for our observations. It ties together all the facts about something, providing an explanation that fits all the observations and can be used to make predictions. In science, the theory is the ultimate goal, the explanation. It’s as close to proven as anything in science can be. Image: Timeline evolution of life on Wikimedia

I recently saw a question on Quora and it was like that: “Why is it called the ‘theory of evolution’ but the ‘law of gravity’?” This question is strongly related to a common misconception about evolution: “It is just a theory” – creationists always say “Evolution is just a theory”.

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Life on Earth Animals

A single cell becomes a complete organism in six min. of timelapse

Alpine newt embryo
The alpine newt (scientific name: Ichthyosaura alpestris) is a newt of the salamander order Caudata (or Urodela) in the class of amphibians. The biggest of the males can reach up to 9 cm (3.54 inches), and the females up to 12 cm (4.72 inches) in length. They typically inhabit forests with good access to water in hilly to mountainous regions of Central Europe and mountainous Southern Europe (where they were originally confined to). They also have isolated populations on the northern Iberian Peninsula and in Italy. The species was introduced into the United Kingdom in the 1930s, initially in southern England and since then several populations have become established as far north as Edinburgh. It has also been introduced to the Sierra de Guadarrama in Madrid Province Spain. They populate well in thick deciduous forests, as well as parkland and natural gardens. They are mostly absent in forest-poor areas.

A single cell becomes a complete organism (an alpine newt) in this amazing six pulsing minutes of a timelapse video named “Becoming” published by the Aeon Video channel. A film by Jan van IJken.

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Animals Environment Life on Earth

28% of vertebrates die because of humans on the land