Human Evolution
Studies in evolutionary biology have led to the conclusion that human beings arose from ancestral primates. This association was hotly debated among scientists in Darwin's day. But today there is no significant scientific doubt about the close evolutionary relationships among all primates, including humans.
Many of the most important advances in paleontology over the past century relate to the evolutionary history of humans. Not one but many connecting links—intermediate between and along various branches of the human family tree—have been found as fossils. These linking fossils occur in geological deposits of intermediate age. They document the time and rate at which primate and human evolution occurred.
Scientists have unearthed thousands of fossil specimens representing members of the human family. A great number of these cannot be assigned to the modem human species, Homo sapiens. Most of these specimens have been well dated, often by means of radiometric techniques. They reveal a well-branched tree, parts of which trace a general evolutionary sequence leading from ape-like forms to modem humans.
Paleontologists have discovered numerous species of extinct apes in rock strata that are older than four million years, but never a member of the human family at that great age. Australopithecus, whose earliest known fossils are about four million years old, is a genus with some features closer to apes and some closer to modem humans. In brain size, Australopithecus was barely more advanced than apes. A number of features, including long arms, short legs, intermediate toe structure, and features of the upper limb, indicate that the members of this species spent part of the time in trees. But they also walked upright on the ground, like humans. Bipedal tracks of Australopithecus have been discovered, beautifully preserved with those of other extinct animals, in hardened volcanic ash. Most of our Australopithecus ancestors died out close to two-and-a-half million years ago, while other Australopithecus species, which were on side branches of the human tree, survived alongside more advanced hominids for another million years.
Distinctive bones of the oldest species of the human genus, Homo, date back to rock strata about 2.4 million years old. Physical anthropologists agree that Homo evolved from one of the species of Australopithecus. By two million years ago, early members of Homo had an average brain size one-and-a-half times larger than that of Australopithecus, though still substantially smaller than that of modem humans. The shapes of the pelvic and leg bones suggest that these early Homo were not part-time climbers like Australopithecus but walked and ran on long legs, as modem humans do. Just as Australopithecus showed a complex of ape-like, human-like, and intermediate features, so was early Homo intermediate between Australopithecus and modem humans in some features, and dose to modem humans in other respects. The earliest
FAQs
What is science according to the National Academy of Sciences? ›
Science is a particular way of knowing about the world. In science, explanations are limited to those based on observations and experiments that can be substantiated by other scientists. Explanations that cannot be based on empirical evidence are not a part of science.
What is the conclusion of the scientific subject? ›Scientific conclusions should be written after the first four steps of the scientific method are completed. They are Question, Hypothesize, Experiment, Analyze, and then finally Conclude. The conclusions should include contextual information, experimental results, analysis, and the conclusion drawn from that data.
What are the conclusion of the characteristics of science? ›Conclusions of science are reliable, though tentative
But just as the word “theory” means something special to the scientist, so too does the word “tentative.” Science's conclusions are not tentative in the sense that they are temporary until the real answer comes along.
The Act to Incorporate the National Academy of Sciences, also known as the Academy Charter, was signed by President Lincoln on 3 March 1863, establishing the Academy as an independent honorary and consulting body with its own governance and structure.
Why is the National Academy of Sciences important? ›The National Academies of Sciences, Engineering, and Medicine provide independent, objective advice to inform policy with evidence, spark progress and innovation, and confront challenging issues for the benefit of society.
Is National Academy of Sciences reputable? ›PNAS is one of the world's most-cited and comprehensive multidisciplinary scientific journals, publishing more than 3,200 research papers annually. The journal's content spans the biological, physical, and social sciences and is global in scope.
How do you write a good conclusion for a science essay? ›- State your conclusions in clear, simple language.
- Do not simply reiterate your results or the discussion.
- Indicate opportunities for future research, as long as you haven't already done so in the discussion section of your paper.
My hypothesis was that Energizer would last the longest in all of the devices tested. My results do support my hypothesis. I think the tests I did went smoothly and I had no problems, except for the fact that the batteries recover some of their voltage if they are not running in something.
What are three important characteristics of science? ›- Objectivity: Scientific knowledge is objective. ...
- Verifiability: Science rests upon sense data, i.e., data gathered through our senses—eye, ear, nose, tongue and touch. ...
- Ethical Neutrality: ...
- Systematic Exploration: ...
- Reliability: ...
- Precision: ...
- Accuracy: ...
- Abstractness:
Five key descriptors for the scientific method are: empirical, replicable, provisional, objective and systematic.
What are the three characteristics of science? ›
Science is a general way of understanding the natural world. Its three fundamental features are systematic empiricism, empirical questions, and public knowledge.
Where was the Academy of Sciences founded in 1666? ›In 1666, the Paris Academy of Sciences was founded by Jean-Baptiste Colbert. This foundation had several political and scientific dimensions, which will be discussed in a synthetic way.
What is the history of the National Academy of Sciences? ›The National Academy of Sciences was established in 1863 by an Act of Congress, signed by President Lincoln, as a private, nongovernmental institution to advise the nation on issues related to science and technology. Members are elected by their peers for outstanding contributions to research.
Who supported the National Academy of Sciences? ›The immediate roots of the NAS can be traced back to the early 1850s and a group of scientists based largely in Cambridge, Massachusetts. The group enlisted the support of Massachusetts Senator Henry Wilson, who helped draft a bill for the incorporation of the National Academy of Sciences.
What is a member of the National Academy of Sciences? ›Election to membership is one of the highest honors that a scientist, engineer, or medical professional can receive. Although no formal duties are involved, members of the National Academy of Sciences and the National Academy of Engineering are invited to participate in the governance and advisory activities.
What is the National Academy of Sciences Award for scientific discovery? ›The NAS Award for Scientific Discovery is presented every two years to recognize an accomplishment or discovery in basic research, achieved within the previous five years, that is expected to have a significant impact on one or more of the following fields: astronomy, biochemistry, biophysics, chemistry, materials ...
What does National Academy of Science and Technology do? ›The National Academy of Science and Technology (NAST) advises the President on matters related to science and technology; engages in projects and programs designed to promote scientific productivity; and, embarks on programs traditionally and internationally expected of an academy of science.
When was the National Academy of Sciences? ›The National Academy of Sciences (NAS) was signed into being by President Abraham Lincoln on March 3, 1863.