4 Global Forest Maps to See the Forest for the Trees
Basic facial-detection technology was used to select all images which showed a single face of sufficient size and clarity to subject to analysis. This left 35, pictures of 14, people, with gay and straight, male and female, all represented evenly. When the resulting model was run on data which it had not seen before, it far outperformed humans at distinguishing between gay and straight faces. In both cases the level of performance far outstrips human ability to make this distinction. This aligns with research which suggests humans can determine sexuality from faces at only just better than chance. As fetuses develop in the womb, they are exposed to various levels of hormones, in particular testosterone.
Accuracy of Fossils and Dating Methods
Forests keep rivers clean. They prevent soil erosion. They prevent landslides and avalanches. They are carbon sinks because they absorb over one-fifth of carbon emissions caused by fossil fuels. But our forests are disappearing:
Radiocarbon dating (also referred to as carbon dating or carbon dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon.. The method was developed in the late s by Willard Libby, who received the Nobel Prize in Chemistry for his work in It is based on the fact that radiocarbon (
These formations may have resulted from carcass burial in an anoxic environment with minimal bacteria, thus slowing decomposition. Stromatolites Lower Proterozoic stromatolites from Bolivia , South America Stromatolites are layered accretionary structures formed in shallow water by the trapping, binding and cementation of sedimentary grains by biofilms of microorganisms , especially cyanobacteria. While older, Archean fossil remains are presumed to be colonies of cyanobacteria , younger that is, Proterozoic fossils may be primordial forms of the eukaryote chlorophytes that is, green algae.
One genus of stromatolite very common in the geologic record is Collenia. The earliest stromatolite of confirmed microbial origin dates to 2. The most widely supported explanation is that stromatolite builders fell victims to grazing creatures the Cambrian substrate revolution , implying that sufficiently complex organisms were common over 1 billion years ago. Factors such as the chemistry of the environment may have been responsible for changes.
Cyanobacteria as well as extremophile Gammaproteobacteria are thought to be largely responsible for increasing the amount of oxygen in the primeval earth’s atmosphere through their continuing photosynthesis. Cyanobacteria use water , carbon dioxide and sunlight to create their food. A layer of mucus often forms over mats of cyanobacterial cells.
Everything Worth Knowing About … Scientific Dating Methods
Such time determinations are made and the record of past geologic events is deciphered by studying the distribution and succession of rock strata, as well as the character of the fossil organisms preserved within the strata. Grand Canyon wall cutaway diagram showing the ages of the rock layers. According to a long-standing principle of the geosciences, that of superposition, the oldest layer within a sequence of strata is at the base and the layers are progressively younger with ascending order.
Scientific American is the essential guide to the most awe-inspiring advances in science and technology, explaining how they change our understanding of the world and shape our lives.
High School Statutory Authority: Students shall be awarded one credit for successful completion of this course. Chemistry or concurrent enrollment in Chemistry. This course is recommended for students in Grades 10, 11, or In Aquatic Science, students study the interactions of biotic and abiotic components in aquatic environments, including impacts on aquatic systems. Investigations and field work in this course may emphasize fresh water or marine aspects of aquatic science depending primarily upon the natural resources available for study near the school.
Students who successfully complete Aquatic Science will acquire knowledge about a variety of aquatic systems, conduct investigations and observations of aquatic environments, work collaboratively with peers, and develop critical-thinking and problem-solving skills.
4 Global Forest Maps to See the Forest for the Trees
At the time that Darwin’s On the Origin of Species was published, the earth was “scientifically” determined to be million years old. By , it was found to be 1. In , science firmly established that the earth was 3. Finally in , it was discovered that the earth is “really” 4.
When it comes to determining the age of stuff scientists dig out of the ground, whether fossil or artifact, “there are good dates and bad dates and ugly dates,” says paleoanthropologist John Shea of .
The Radiometric Dating Game Radiometric dating methods estimate the age of rocks using calculations based on the decay rates of radioactive elements such as uranium, strontium, and potassium. On the surface, radiometric dating methods appear to give powerful support to the statement that life has existed on the earth for hundreds of millions, even billions, of years.
We are told that these methods are accurate to a few percent, and that there are many different methods. We are told that of all the radiometric dates that are measured, only a few percent are anomalous. This gives us the impression that all but a small percentage of the dates computed by radiometric methods agree with the assumed ages of the rocks in which they are found, and that all of these various methods almost always give ages that agree with each other to within a few percentage points.
Since there doesn’t seem to be any systematic error that could cause so many methods to agree with each other so often, it seems that there is no other rational conclusion than to accept these dates as accurate. However, this causes a problem for those who believe based on the Bible that life has only existed on the earth for a few thousand years, since fossils are found in rocks that are dated to be over million years old by radiometric methods, and some fossils are found in rocks that are dated to be billions of years old.
If these dates are correct, this calls the Biblical account of a recent creation of life into question. After study and discussion of this question, I now believe that the claimed accuracy of radiometric dating methods is a result of a great misunderstanding of the data, and that the various methods hardly ever agree with each other, and often do not agree with the assumed ages of the rocks in which they are found.
I believe that there is a great need for this information to be made known, so I am making this article available in the hopes that it will enlighten others who are considering these questions. Even the creationist accounts that I have read do not adequately treat these issues. At the start, let me clarify that my main concern is not the age of the earth, the moon, or the solar system, but rather the age of life, that is, how long has life existed on earth.
Everything Worth Knowing About Scientific Dating Methods This dating scene is dead. The good dates are confirmed using at least two different methods, ideally involving multiple independent labs for each method to cross-check results. Sometimes only one method is possible, reducing the confidence researchers have in the results.
Amino Acid Dating Introduction. Amino acid dating has an important attribute in common with Carbon 14 dating. While most other dating mechanisms date the rock surrounding fossils, both Amino Acid and Carbon 14 dating methods, date the actual fossil itself.
Renaissance Now, let’s look at some specific examples. One type of atom that does not normally react is Neon. See the picture to the left. It already has the correct number of electrons in it’s outside electron layer so Neon does not react. Neon, along with Helium and Argon are known as non-reacting gasses because they do not need to react to be stable.
Other types of atoms such as Hydrogen, Carbon, and Oxygen do not have the correct number of electrons to be stable by itself. Instead they have to share electrons in molecules to get the correct number of electrons in their outside electron layer. Since we only have to look at the atom that is in the center of the molecule to find out it’s shape, we will concentrate only on Carbon and Oxygen. All the molecules illustrated on this page either have a Carbon or an Oxygen as the center atom.
Share via Print Broken bones of a mastodon found in Southern California are said to demonstrate that humans were present in the Americas , years ago. For decades archaeologists thought they knew the answers to these questions. Based on the available evidence, it seemed big game hunters from Asia known as the Clovis people were the first to blaze that trail, trekking across the now submerged land mass of Beringia to enter the New World around 13, years ago.
But starting in the early s signs of an earlier human presence in the Americas started to crop up, eroding support for the so-called Clovis first model. A new understanding of how people finally conquered the New World began to take shape:
Articles home page Creation vs. Evolution 0. Introduction and table of contents The following is an organized presentation on the creation vs. evolution controversy.
Share shares Their results suggest both skulls were in fact those of wolves – not the earliest dogs as claimed in other studies. This means that the earliest fossil evidence for domesticated dogs still dates to about 15, years ago – a time when humans started forming permanent settlements and farming, said the team. The team used scans and 3D visualisation software to study the shape and size of the two skulls and compare the data with measurements from the skulls of other dogs and wolves – both modern-day and ancient ‘Scientists have been eager to put a collar on the earliest domesticated dog,’ said biologist and study co-author Abby Drake of Skidmore College, New York.
In a study last year, they found that the key difference between wolves and dogs is that centuries of eating human food has meant dogs possess genes for digesting starches, allowing them to thrive on a human diet. The Swedish team say the dog’s love of human food supports the idea that dogs became domesticated by lingering around human settlements.
Lindblad-Toh and her team catalogued the genetic changes involved in domestication by looking for differences between the genomes of 12 wolves and 60 dogs from 14 different breeds.