It’s ironic how calling a person a “monkey” or “orangutan” is considered offensive when we all know that humans are descended from these apes. Well, sometimes it is hard to find logic in the customs and practices of our society, but if you are willing to find the path of evolution that turned monkeys into the modern men, you may find the details in the fossil records.Continue reading The Significance of Fossils in Revealing the Evolution on Earth
Back in December 1990, during its flyby of Earth, NASA’s Galileo spacecraft, which studied the planet Jupiter and its moons, as well as several other Solar System bodies, pointed its instruments towards Earth, at the urging of Carl Sagan. And, it has found evidence of life on our planet. This can be a key to detect vegetation on exoplanets – which is a key to a possible i
In a paper published on Nature, researchers wrote “The Galileo spacecraft found evidence of abundant gaseous oxygen, a widely distributed surface pigment with a sharp absorption edge in the red part of the visible spectrum, and atmospheric methane in extreme thermodynamic disequilibrium. Together, these are strongly suggestive of life on Earth.”Continue reading Earth can be a model for detecting vegetation on exoplanets
Birds (Aves) range in size and weight from the 5 cm (2 in) and 1.6-2 grams bee hummingbird to the 2.75 m (9 ft) and 104-156 kg (229-344 lbs) ostrich. Here are the top 15 largest bird species in the world (by body weight).
Birds form one of six basic animal groups, with the others being amphibians, fish, invertebrates, mammals and reptiles. They are endothermic vertebrates, characterized by feathers, toothless beaked jaws, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton. They reproduce by laying of hard-shelled eggs (eggs fertilize inside the female). The fossil record indicates that birds are the last surviving group of dinosaurs. So, they are also termed avian dinosaurs.
Around 66 million years ago, an asteroid or comet at least 10 kilometers (6 miles) in diameter impacted a few miles from the present-day town of Chicxulub in Mexico (hence it is dubbed as the “Chicxulub impactor”), at around 64,000 kilometers per hour (40,000 mph). The impact has created a crater (Chicxulub crater) more than 180 km (110 miles) in diameter. But, what’s more, the energy of the impact (which is equivalent of about ten billion Hiroshima atom bombs) vaporized the rock which was rich in sulfur compounds, filling the air with a thick cloud of dust, similar to that created by a catastrophic volcanic eruption.
This cloud blocked out the sun at least for a decade and caused a global, dark winter: even in the tropics the temperatures were barely above freezing, and the average global temperature was below 0°C (32°F). Before the impact, the average global temperature was around 26°C (47°F), so this means a huge drop. And the recovery time was more than 30 years! The dinosaurs which had dominated the Earth for more than 150 million years were used to living in a lush climate and were already in decline, so non-avian dinosaurs couldn’t survive after the last deadly blow.
Hint: they are all space rocks. But, there are some differences. The biggest difference between an asteroid and a comet, for example, is what they are made of.
In 1981, when I was nine years old, my father took me to see Raiders of the Lost Ark. Although I had to squint my eyes during some of the scary scenes, I loved it – in particular because I was fairly sure that Harrison Ford’s character was based on my dad. My father was a palaeontologist at the University of Chicago, and I’d gone on several field trips with him to the Rocky Mountains, where he seemed to transform into a rock-hammer-wielding superhero.
I stumbled upon an amazing web page showing what did ancient Earth look like. On “Dinosaur Pictures and Facts” web page (dinosaurpictures.org), there’s also an interactive animation. On this page, you can either select the years (i.e. 600 million years ago) or jump to a particular event (i.e. first multicellular life) and see how ancient Earth did look like then. You can also remove the clouds and stop the Earth’s rotation if you want to.
Are we alone in the Universe? Or any other life forms exist out there? A new study, published on the Proceedings of the National Academy of Sciences of the United States of America (PNAS)Notes 1 suggests that the life emerged so early on Earth – it should be widespread. In other words, the Universe should be filled with life.
The story goes back to 1982. 35 years ago, UCLA Scholar and Pioneer in Study of the Evolution of Life, J. William Schopf collected 3.465-billion-year-old fossils from the Apex Chert in
According to the scientists who drilled into the Chicxulub crater buried underneath the Yucatán Peninsula and the Gulf of Mexico, the asteroid hit the “worst possible place”. They summarized their findings so far in a BBC Two documentary titled “The Day The Dinosaurs Died“. The documentary presented by professors Alice Roberts and Ben Garod.
Identifying the largest dinosaurs ever lived isn’t an easy task, because it’s very rare to unearth a complete fossil. Furthermore, only a tiny percentage of these amazing animals ever fossilized, and most of these “lucky” bodies will remain buried underground forever. So, we may never know exactly what dinosaur was the biggest (or the tiniest) ever.
Despite this fact, size always has been one of the most interesting aspects of these prehistoric animals. There are extreme variations in their size, from the tiny hummingbirds, which can weigh as little as three grams, to the titanosaurs, which could weigh as much as 70 tonnes, or even more.
Here are the largest dinosaurs ever lived.Continue reading Largest dinosaurs ever lived