Answer:
Darwin conducted an experiment with breeding pigeons.
Explanation:
The pigeons provided the perfect animal to test his theory of selection for quite a number of reasons including its trait diversity from wing structures to color patterns to size to flight patterns. From these experiments he concluded that by natural selection of randomly occurring traits that make species better suited for survival and reproduction, evolve in the astounding diversity of organisms on Earth today.
<em>(not my words) </em>
Beavers are descendants of land-dwelling rodents similar to rats. The beavers however have adapted their body shape to live in water bodies like ponds and lakes. This can be hypothesised by saying that the early rodents or the ancestors of beavers were forced to find food in the waters. They lacked the flat tail and the webbed feet. With time the need to increase their ability to catch fishes and floating insects, the rodents with flatter tail and a bigger flat webbed feet gradually evolved. The rodents with flatter tails and webbed feet became adjusted to the life on water and became the modern day beavers.
Answer: D. Adaptations help organisms survive and reproduce in a particular environment.
Explanation:
An adaptation can be define as the changes that occur in the behavior, structure and physiology of the organism so that organism become suited to survive and reproduce in the adverse environment. Adaptation results due to evolution of the living organisms through the process of natural selection as a result of interaction of the organism with the changing or unsuitable environment.
<span><span>Radio waves: If our eyes could see radio waves, we could (in theory) watch TV programs just by staring at the sky! Well not really, but it's a nice idea. Typical size: 30cm–500m. Radio waves cover a huge band of frequencies, and their wavelengths vary from tens of centimeters for high-frequency waves to hundreds of meters (the length of an athletics track) for lower-frequency ones. That's simply because any electromagnetic wave longer than a microwave is called a radio wave.</span><span>Microwaves: Obviously used for cooking in microwave ovens, but also for transmitting information in radar equipment. Microwaves are like short-wavelength radio waves. Typical size: 15cm (the length of a pencil).</span><span>Infrared: Just beyond the reddest light we can see, with a slightly shorter frequency, there's a kind of invisible "hot light" called infrared. Although we can't see it, we can feel it warming our skin when it hits our face—it's what we think of as radiated heat. If, like rattlesnakes, we could see infrared radiation, it would be a bit like having night-vision lenses built into our heads. Typical size: 0.01mm (the length of a cell).</span><span>Visible light: The light we can actually see is just a tiny slice in the middle of the spectrum.</span><span>Ultraviolet: This is a kind of blue-ish light just beyond the highest-frequency violet light our eyes can detect. The Sun transmits powerful ultraviolet radiation that we can't see: that's why you can get sunburned even when you're swimming in the sea or on cloudy days—and why sunscreen is so important. Typical size: 500 nanometers (the width of a typical bacteria).</span><span>X rays: A very useful type of high-energy wave widely used in medicine and security. Find out more in our main article on X rays. Typical size: 0.1 nanometers (the width of an atom).</span><span>Gamma rays: These are the most energetic and dangerous form of electromagnetic waves. Gamma rays are a type of harmful radiation. Typical size: 0.000001 nanometers (the width of an atomic nucleus).</span></span>
