On average, dogs spend about 12-to-14 hours of the 24-hour cycle sleeping. Older dogs need significant amounts of sleep simply because, as they age, living becomes more difficult. They tire out more easily and need rest in order to function properly. Puppies , like babies, spend a lot of time exhausting energy while playing and exploring their new surroundings. Because of this, they might need as much as 18-to-20 hours of sleep to recoup! And of course, all dogs need sleep, but it tends to be the bigger breeds that are known for constant dozing.
If a car is powered by electricity, however, the energy has to be stored in batteries that have a much lower energy density than gasoline does. To carry 300 miles’ worth of energy, an electric car would need a lot of very heavy batteries. Furthermore, it is difficult to deliver the energy needed to power an electric car in an acceptably short time. Modern battery-powered cars charge at a rate roughly a thousand times slower than the rate of refueling with gasoline, meaning overnight charging is required to store enough energy for a day’s worth of driving. For most Americans in the fast-paced 21st century, that’s an unacceptably long time span.
Plant circadian rhythms tell the plant what season it is and when to flower for the best chance of attracting pollinators. Behaviors showing rhythms include leaf movement, growth, germination, stomatal/gas exchange, enzyme activity, photosynthetic activity, and fragrance emission, among others.  Circadian rhythms occur as a plant entrains to synchronize with the light cycle of its surrounding environment. These rhythms are endogenously generated and self-sustaining and are relatively constant over a range of ambient temperatures. Important features include two interacting transcription-translation feedback loops: proteins containing PAS domains, which facilitate protein-protein interactions; and several photoreceptors that fine-tune the clock to different light conditions. Anticipation of changes in the environment allows appropriate changes in a plant's physiological state, conferring an adaptive advantage.  A better understanding of plant circadian rhythms has applications in agriculture, such as helping farmers stagger crop harvests to extend crop availability and securing against massive losses due to weather.