1.
Natural selection is:
the idea that traits that help animals survive and reproduce become more frequent.
embryos sharing features in the late stages of development.
that all vertebrates have seven vertebrae in their necks.
3.
Humans, mice and giraffes share a common ancestor. What trait helps scientists understand that these organisms share a common ancestor?
They are all very different in size
They all have seven vertebrae in their necks
They once had wings
They are all bipedal
They all share homologous structures such as the structure of the forelimb as seen in their anatomy.
1. Natural selection is the idea that traits that help animals survive and reproduce become more frequent. It is one of the key mechanisms of evolution proposed by Charles Darwin. In populations of organisms, individuals with advantageous traits are more likely to survive and pass on their genes to the next generation. Over time, this leads to the accumulation of beneficial traits in the population, increasing the overall fitness of the species.
1. Natural selection is the idea that traits that help animals survive and reproduce become more frequent.
To understand natural selection, it is important to learn about the theory of evolution. Evolution is the gradual change in the inherited characteristics of species over generations. The primary mechanism driving evolution is natural selection.
Natural selection is a process by which certain traits or characteristics within a population become more or less common over time. The key concept is that individuals with advantageous traits are more likely to survive and pass on those traits to their offspring, while individuals with disadvantageous traits are less likely to survive and reproduce.
Here's how natural selection works:
1. Variation: Within a population, individuals exhibit a range of traits due to genetic differences or mutations. For example, some individuals may have longer beaks, while others have shorter beaks in a bird population.
2. Selective Pressure: Environmental factors, such as food availability or predation, create a selective pressure. In our example, if a bird population lives mostly on a diet of long tubular flowers, birds with longer beaks might have an advantage in obtaining nectar and, therefore, surviving and reproducing.
3. Differential Survival and Reproduction: Individuals with traits that are better suited to the environment have higher chances of survival and reproduction. Birds with longer beaks can easily access nectar from the flowers, increasing their chances of survival and breeding.
4. Inheritance: Offspring inherit traits from their parents. In our example, the birds with longer beaks are more likely to produce offspring with longer beaks, passing on the advantageous trait.
5. Accumulation of Traits: Over time, as advantageous traits are consistently passed down through generations, they become more common in the population. In our example, the bird population may see a gradual increase in the average beak length over generations.
It's important to note that natural selection operates on a population level rather than an individual level. It is a gradual and ongoing process that leads to the adaptation of species to their environments over long periods of time.
To recap, natural selection is the process by which traits that improve an organism's chance of survival and reproduction become more prevalent in a population over time. By understanding this concept, we can gain insights into how species evolve and adapt to their environments.