Earth - How do we know that evolution is really happening? Evolution is one of the greatest theories in all of science.
It sets out to explain life: specifically, how the first simple life gave rise to all the huge diversity we see today, from bacteria to oak trees to blue whales. For scientists, evolution is a fact. Molecular Life Sciences — Top 5 misconceptions about evolution: A guide to... Introduction: Evolution - life - 04 September 2006. Read full article Continue reading page |1|2 In 1859 Charles Darwin published his theory of natural selection amid an explosion of controversy.
Like the work of Copernicus in the 16th century revealing the movement of the Earth, Darwin's idea shook the foundations of the establishment and profoundly altered humanity's view of its place in the universe. Today evolution is the unifying force in modern biology; it ties together fields as disparate as genetics, microbiology and palaeontology. It is an elegant and convincing explanation for the staggering diversity of Earth's five million or more living species. Evolution has several facets.
Darwin argued that all individuals struggle to survive on limited resourses, but some have small, heritable differences that give them a greater chance of surviving or reproducing, than individuals lacking these beneficial traits. Eventually these advantageous traits become the norm. Sex wars Species spawning. How 60 of the weirdest birds are related. A family called cotingas include some of the loudest, weirdest-looking, brightest, least-understood birds on the planet.
Some have bulbous crests, long fleshy wattles, or Elvis-worthy pompadours. Others have shockingly bright feathers—electric blue, deep purple, or screaming orange. How did they get that way? What twisting evolutionary path resulted in the origin of more than 60 species that barely seem to be related each other? A new phylogeny, or evolutionary “tree of life,” makes finding answers to these questions possible. Evolution in the Slow Lane. One late spring weekend a few years back, my wife and I drove out to Delaware to see an amazingly old tradition.
Knowing that both time and tide were critical, we had asked around for the best spot and right hour. Primate Hook National Wildlife Refuge at sunset was the most popular answer, and so, after a day of reading in camp, we pulled up to a beach shaded orange by the evening light. The Evolution of Color Vision. The Evolution of Color Vision Copyright © 1992-1997 by Mickey Rowe Opsin Genes ob Bales brought up an interesting topic in a recent post (well, it was recent when I started writing this).
The topic is "evolution and color vision". Bob is apparently under some misconceptions either about color vision, or at least what evolutionary theory might predict about it. In a series of four posts beginning with this one, I want to ramble on and on about some of the background you might want to know if you were going to make some meaningful statements about evolution and color vision. I'm going to start by describing a tiny fraction of what's well known about the molecular biology and biochemistry involved in visual transduction. The Origins of the Anger Face. In the U.S., the thumbs-up is typically a gesture that everything’s just hunky-dory—but in the Middle East, it implies that the gesturer is about to do something decidedly unfriendly with that thumb and another person’s anatomy.
In Brazil, the “OK” sign—another innocuous move in America—is an obscene way of saying that things are definitely not OK. And in Greece, facing your palm towards another person doesn’t imply a sassy 90s-throwback “talk to the hand” reference so much as a desire to rub excrement in another person’s face. But while these particular pieces of body language differ wildly in meaning depending on where they take place, the response to an offensive gesture anywhere in the world will likely look the same: nostrils flared, lips thinned, chin pushed up and out.
In other words, the natural human anger face. Evolution Resources: Students. Évolution. Where Genes Come From. In today’s New York Times, I’ve written a story about a simple but important question: where do new genes come from?
Some four billion years ago, when cellular life emerged, a typical primordial microbe likely had only a small set of genes. Today, however, genes abound. We, for example, have 20,000 genes that encode proteins. Dogs have their own set, and so do starfish and fireflies and willow trees and every other species on Earth. The-continuing-evolution-of-genes. The Dramatic Evolution Of The Human Face Over 7 Million Years. The Dramatic Evolution Of The Human Face Over 7 Million Years Scientists believe they've been able to successfully map the evolutionary changes to the human face over the past 7 million years.
And whilst there's a certain amount of assumption and theory when you're dealing with such a ginormous timespan, much of the what you're about to see is based on hard evidence. Over the years tiny bones, skulls, teeth and fragments have been unearth and discovered across the globe. Each of those provide clues as to specific composition and structure of the human face.
Evolution - A-Z - Frequency-dependent selection. Frequency-dependent selection occurs when the fitness of a genotype depends on its frequency.
It is possible for the fitness of a genotype to increase (positively frequency-dependent) or decrease (negatively frequency-dependent) as the genotype frequency in the population increases. Examples of frequency dependence can arise in systems of mimicry: • Natural selection may favor non-poisonous butterflies that have the same color pattern as poisonous butterflies. (e-book)Darwin - THE DESCENT OF MAN (1) Evolution: Frequently Asked Questions. Evolution. Introduction to Evolutionary Biology. Introduction to Evolutionary Biology Version 2 Copyright © 1996-1997 by Chris Colby[Last Update: January 7, 1996] volution is the cornerstone of modern biology.
It unites all the fields of biology under one theoretical umbrella. It is not a difficult concept, but very few people -- the majority of biologists included -- have a satisfactory grasp of it. One common mistake is believing that species can be arranged on an evolutionary ladder from bacteria through "lower" animals, to "higher" animals and, finally, up to man. Mistakes permeate popular science expositions of evolutionary biology. Misunderstandings about evolution are damaging to the study of evolution and biology as a whole. This is a brief introduction to evolutionary biology. What is Evolution? Top 10 Myths About Evolution – with Downloadable PDF. Email If you have been looking for a simple, easy to follow quick guide to evolution… we’ve got it.
Our friends at the Skeptics Society gave us permission to reprint this. Below is the text. Learn it. Share it. Original Text: Giles Fraser says scientists are replacing theologians. Some thoughts on that. This transition can of course only be for the best. And this good-humoured article is definitely a step up from the "science is the new religion" trope I feared from the headline.
Fraser talks about two desires that many (though perhaps not all) of us have. One is to understand the world we live in; the other is to find a meaning to it. I see these as quite distinct, though it's possible Fraser does not. On the first, the understanding front, physics – or science in general, I would say – does seem to have theology beaten, for the same reason that actually looking at the clues gives you a better chance of doing a crossword.
Your Inner Fish: Book and PBS documentary on Tiktaalik and Neil Shubin. Photo courtesy PBS We all know the Darwin fish, the car-bumper send-up of the Christian ichthys symbol, or Jesus fish. Unlike the Christian symbol, the Darwin fish has, you know, legs. But the Darwin fish isn't merely a clever joke; in effect, it contains a testable scientific prediction. If evolution is true, and if life on Earth originated in water, then there must have once been fish species possessing primitive limbs, which enabled them to spend some part of their lives on land. And these species, in turn, must be the ancestors of four-limbed, land-living vertebrates like us.