Which is the best evidence that two species have a common ancestor?
Homologous structures provide evidence for common ancestry, while analogous structures show that similar selective pressures can produce similar adaptations (beneficial features). Similarities and differences among biological molecules (e.g., in the DNA sequence of genes) can be used to determine species’ relatedness.
What are two examples of types of body structures that provide evidence of a common ancestor?
Homologous structures are structures that have a common function and suggest common ancestry. For example, homologous structures include the limbs of mammals, such as bats, lions, whales, and humans, which all have a common ancestor. Different mammals may use their limbs for walking, running, swimming or flying.
Which is an example of a structural homology?
Homologous Structures Humans Share With Animals Here are some examples of homologous structures that humans share with other creatures from the animal kingdom. A dolphin’s flipper, a bird’s wing, a cat’s leg, and a human arm are considered homologous structures.
Which of the following explains the presence of proteaceae in both Australia and South America?
The presence of Proteaceae in Australia, southern Africa, and South America is best explained by the plant family’s presence there prior to the southern supercontinent Gondwana breaking up (Figure).
How do bones support the theory of evolution?
Another type of evidence for evolution is the presence of structures in organisms that share the same basic form. For example, the bones in the appendages of a human, dog, bird, and whale all share the same overall construction (Figure 2) resulting from their origin in the appendages of a common ancestor.
Is evolution a theory or a hypothesis?
The theory of evolution is not a hypothesis, but the scientifically accepted explanation of the incontrovertible fact that life and its many forms has changed over the years. As a key principle of science, evolutionary theory cannot be dismissed or diminished by characterizing it as mere conjecture or speculation.
Why is evolution a theory?
Darwin and a scientific contemporary of his, Alfred Russel Wallace, proposed that evolution occurs because of a phenomenon called natural selection. In the theory of natural selection, organisms produce more offspring than are able to survive in their environment.
Is Darwin’s theory proven?
(CNN) When Charles Darwin published “On the Origin of Species” in 1859, his evolutionary theories permanently shook up science and the way researchers studied the natural world. And while his seminal work laid the foundation for evolutionary biology, one major point of his was never proven.
Why is Darwin wrong?
What Darwin Got Wrong is a 2010 book by philosopher Jerry Fodor and cognitive scientist Massimo Piattelli-Palmarini, in which the authors criticize Charles Darwin’s theory of natural selection. It is an extension of an argument first presented as “Why Pigs Don’t Have Wings” in the London Review of Books.
What piece of evidence was Darwin missing?
Yet there were two fundamental gaps in his chain of evidence. First, Darwin had no knowledge of the mechanism of heredity. Second, he had no visible example of evolution at work in nature. It is a curious fact that both of these gaps could have been filled during Darwin’s lifetime.