Island gigantism is a biological phenomenon in which the size of animals isolated on an island increases dramatically in comparison to their mainland relatives. Large mammalian carnivores are often absent on islands, due to their large range requirements and/or difficulties in over-water dispersal. In their absence, the ecological niches for large predators may be occupied by birds or reptiles, which can then grow to larger-than-normal size. YAY.
Seven Characteristics of Living ThingsThere are 7 characteristics that determine whether something is animate or inanimate. There are, of course, exceptions. First, I will go over the seven characteristics and then I will give two examples that seem to break the deal, but actually do nothing of the sort.
Living things... 1.Detect and React to external stimuli 2. Use Energy 3. Evolve 4. Grow 5. Reproduce 6. Maintain Homeostasis 7. Are Cellular Now, think for a minute about a mule. A mule exhibits all of these characteristics except for one (reproduction), yet it is still a living creature. And a virus, which is a non-living entity, exhibits 6 of the seven characteristics (exception: being cellular). Strange, but good science always leaves room for interpretation. The Doppler EffectThe Doppler effect is a beautiful principle of relativity and wave frequency. It is the change in wavelength of a wave for an observer moving relative to the source of the wave. The received waves on a siren, for example, on a passing emergency vehicle of sorts will start out at a higher frequency as the vehicle approaches the observer, will be equal to the transmitted waves at the moment of passing the observer, and will lower in frequency during the recession. It is not actually the frequency that changes, itis the wavelength. So, the siren on an ambulance will start out higher than its stationary pitch while approaching you, will be at its stationary pitch while next to you, and will be lower than its stationary pitch as it passes away from you.  |
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