How long ago did the first humans appear on Earth mastering biology?

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The human lineage diverged from other primates around 6-7 million years ago, and our species originated only about 195,000 years ago.

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Which of the following are consequences of continental drift quizlet?

What are the effects of continental drift? it alters the habitats organisms live in. Causes climate changes, promotes allopatric speciation, helps explain geographic distribution of extinct organisms.

How does continental drift explain the uniqueness of Australian fauna?

How does continental drift explain the uniqueness of Australian fauna? The subsequent separation of the southern continents formed an island of marsupials. Which period had the greatest increase in the number of extant species?

Which of the cells shown in the figure are eukaryotic cells mastering biology?

Which of the cells shown in the figure are eukaryotic cells? Explanation: All eukaryotic cells have a nucleus, endomembrane system, and mitochondria. So, of the cells shown, 5, 6, and 7 are eukaryotic cells.

How can we determine the age of fossils mastering biology?

The age of fossils can sometimes be determined by radiometric dating, which is based on the constant rate of decay of radioactive isotopes. The time required for half of a radioactive isotope to decay is called the half-life of that isotope. For example, the isotope carbon-14 has a half-life of 5,730 years.

Who was the first scientist to state that species change over time?

Jean Baptiste Lamarck (1744–1829) was an important French naturalist. He was one of the first scientists to propose that species change over time.

Which of the following are consequences of continental drift?

Continental drift alters the physical geography and climate of Earth, as well as the extent to which organisms are geographically isolated. Because these factors affect extinction and speciation rates, continental drift has a major impact on life on Earth.

What factors lead to extinctions adaptations and or the emergence of new species?

Extinction is often caused by a change in environmental conditions. When conditions change, some species possess adaptations that allow them to survive and reproduce, while others do not. If the environment changes slowly enough, species will sometimes evolve the necessary adaptations, over many generations.

What are leading hypotheses for the formation of life on Earth quizlet?

The formation of the earth according to the most widely held hypothesis, The Big Bang Theory, was that 4.6 billion years ago, a cloud of rocks and dust condensed due to gravitational pulls, and bombardments by ice and rocks caused intense heat that vaporized water on earth.

What has been the effect of continental drift on biodiversity?

“Because of the plate tectonic processes, new habitats emerged in different locations over the course of millions of years, while others merged or disappeared. These dynamic structures encouraged the relocation of the focal point of species diversity,” says the landscape ecology professor.

How does continental drift cause extinction?

As continents heaved upward, pushed by the movement of tectonic plates, ocean currents were redirected and global sea levels fell. The Interior Seaway, for example, which once divided North America in half, simply drained away as the Colorado Plateau rose thousands of feet.

What type of speciation is continental drift?

‘ Allopatric speciation is thus speciation that occurs through geographic isolation of two populations or groups of populations. In this scenario, a population is split by some geographic barrier, such as a mountain range or river for terrestrial organisms, or a land mass for aquatic organisms.

How does continental drift affect living organisms See Concept 25.4 page?

How does continental drift affect living organisms? It causes climate change, which puts selective pressure on organisms. It causes changes in habitats, such as when large amounts of shallow marine habitat were lost in the formation of Pangaea.

What was the independent variable in this experiment mastering biology?

What was the independent variable in this experiment? [The independent variable was the possible control element that was deleted from the experimental sequences because the researchers manipulated that variable in each treatment.]

Which fact is the basis for using the fossil record as evidence that evolution has taken place?

Which fact is the basis for using the fossil record as evidence that evolution has taken place? in undisturbed layers of rock strata, the older fossils are found in the deeper layers.

How do scientists help historians know how old things are?

Radiocarbon dating is the most common method by far, according to experts. This method involves measuring quantities of carbon-14, a radioactive carbon isotope — or version of an atom with a different number of neutrons.

How can a fossil freshwater reptile be found in both Brazil and West Africa areas separated today by a wide expanse of ocean?

How can a fossil freshwater reptile be found in both Brazil and West Africa, areas separated today by a wide expanse of ocean? This is an indication that at the time this reptile flourished, the South American and African plates had not yet spread apart.

Is evolution a fact?

Evolution, in this context, is both a fact and a theory. It is an incontrovertible fact that organisms have changed, or evolved, during the history of life on Earth. And biologists have identified and investigated mechanisms that can explain the major patterns of change.

When did schools start teaching evolution?

Kentucky passed a state law in 1976 that states public school teachers who teach evolution may also teach “the theory fo creation as presented in the Bible.” The law was re-adopted in 1990. In 1998, the Board of Education voted to insert the word “evolution” into the science curriculum guidelines for the first time.

Who created evolution?

Charles Darwin is commonly cited as the person who “discovered” evolution. But, the historical record shows that roughly seventy different individuals published work on the topic of evolution between 1748 and 1859, the year that Darwin published On the Origin of Species.

How does continental drift affect the climate?

Continental motion via the movement of tectonic plates can affect earth’s climate by changing the sizes and locations of both land masses and ice caps, and by altering ocean circulation patterns, which are responsible for transporting heat around the earth, which in turn affect atmospheric circulation processes.

Why is continental drift important?

continental drift, large-scale horizontal movements of continents relative to one another and to the ocean basins during one or more episodes of geologic time. This concept was an important precursor to the development of the theory of plate tectonics, which incorporates it.

How did Pangea affect animals?

As Pangea formed, the extent of shallow water habitats declined, and land barriers inhibited cold polar waters from circulating into the tropics. This is thought to have reduced dissolved oxygen levels in the warm water habitats that remained and contributed to the 95 percent reduction of diversity in marine species.

Will humans go extinct?

Scientists estimate modern humans have been around about 200,000 years, so that should give us at least another 800,000 years. Other scientists believe we could be here another two million years…or even millions of years longer.

What happened to the population of species if they fail to adapt to these changes?

If it changes more rapidly, few adaptive walks will be completed, and the population will be poorly adapted most of the time. If it changes very rapidly selection may be inadequate to restore adaptation quickly enough, and the population will dwindle and eventually become extinct.

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