Near the equator, many species of bird breed all year round. But in temperate and polar regions, the breeding seasons of birds are often sharply defined. They are triggered mainly by changes in day length. If all goes well, the outcome is that birds raise their young when the food supply is at its peak. Most birds are not simply reluctant to breed at other times but they are also physically incapable of doing so. This is because their reproductive system shrinks, which helps flying birds save weight. The main exception to this rule are nomadic desert species. These can initiate their breeding cycle within days of rain. It's for making the most of the sudden breeding opportunity. Also, different species divide the breeding season up in different ways. Most seabirds raise a single brood. In warm regions, however, songbirds may raise several families in a few months. In an exceptionally good year, a pair of House Sparrows, a kind of songbird, can raise successive broods through a marathon reproductive effort.

One factor that may hinder creativity is unawareness of the resources required in each activity in students' learning. Often students are unable to identify the resources they need to perform the task required of them. Different resources may be compulsory for specific learning tasks, and recognizing them may simplify the activity's performance. For example, it may be that students desire to conduct some experiments in their projects. There must be a prior investigation of whether the students will have access to the laboratory, equipment, and chemicals required for the experiment. It means preparation is vital for the students to succeed, and it may be about human and financial resources such as laboratory technicians, money to purchase chemicals, and equipment for their learning where applicable. Even if some of the resources required for a task may not be available, identifying them in advance may help students' creativity. It may even lead to changing the topic, finding alternative resources, and other means.

All translators feel some pressure from the community of readers for whom they are doing their work. And all translators arrive at their interpretations in dialogue with other people. The English poet Alexander Pope had pretty good Greek, but when he set about translating Homer's Iliad in the early 18th century he was not on his own. He had Greek commentaries to refer to, and translations that had already been done in English, Latin, and French — and of course he had dictionaries. Translators always draw on more than one source text. Even when the scene of translation consists of just one person with a pen, paper, and the book that is being translated, or even when it is just one person translating orally for another, that person's linguistic knowledge arises from lots of other texts and other conversations. And then his or her idea of the translation's purpose will be influenced by the expectations of the person or people it is for. In both these senses every translation is a crowd translation.

Some people argue that there is a single, logically consistent concept known as reading that can be neatly set apart from everything else people do with books. Is reading really that simple? The most productive way to think about reading is as a loosely related set of behaviors that belong together owing to family resemblances, as Ludwig Wittgenstein used the phrase, without having in common a single defining trait. Consequently, efforts to distinguish reading from nonreading are destined to fail because there is no agreement on what qualifies as reading in the first place. The more one tries to figure out where the border lies between reading and not-reading, the more edge cases will be found to stretch the term's flexible boundaries. Thus, it is worth attempting to collect together these exceptional forms of reading into a single forum, one highlighting the challenges faced by anyone wishing to establish the boundaries where reading begins and ends. The attempt moves toward an understanding of reading as a spectrum that is expansive enough to accommodate the distinct reading activities.

Weber's law concerns the perception of difference between two stimuli. It suggests that we might not be able to detect a 1-mm difference when we are looking at lines 466 mm and 467 mm in length, but we may be able to detect a 1-mm difference when we are comparing a line 2 mm long with one 3 mm long. Another example of this principle is that we can detect 1 candle when it is lit in an otherwise dark room. But when 1 candle is lit in a room in which 100 candles are already burning, we may not notice the light from this candle. Therefore, the Just-noticeable difference (JND) varies as a function of the strength of the signals. For example, the JND is greater for very loud noises than it is for much more quiet sounds. When a sound is very weak, we can tell that another sound is louder, even if it is barely louder. When a sound is very loud, to tell that another sound is even louder, it has to be much louder. Thus, Weber's law means that it is harder to distinguish between two samples when those samples are larger or stronger levels of the stimuli.

Any new resource (e.g., a new airport, a new mall) always opens with people benefiting individually by sharing a common resource (e.g., the city or state budget). Soon, at some point, the amount of traffic grows too large for the "commons" to support. Traffic jams, overcrowding, and overuse lessen the benefits of the common resource for everyone — the tragedy of the commons! If the new resource cannot be expanded or provided with additional space, it becomes a problem, and you cannot solve the problem on your own, in isolation from your fellow drivers or walkers or competing users. The total activity on this new resource keeps increasing, and so does individual activity; but if the dynamic of common use and overuse continues too long, both begin to fall after a peak, leading to a crash. What makes the "tragedy of commons" tragic is the crash dynamic —the destruction or degeneration of the common resource's ability to regenerate itself.

Theoretically, our brain would have the capacity to store all experiences throughout life, reaching the quality of a DVD. However, this theoretical capacity is offset by the energy demand associated with the process of storing and retrieving information in memory. As a result, the brain develops efficient strategies, becoming dependent on shortcuts. When we observe a face, the visual image captured by the eyes is highly variable, depending on the point of view, lighting conditions and other contextual factors. Nevertheless, we are able to recognize the face as the same, maintaining the underlying identity. The brain, rather than focusing on the details of visualization, creates and stores general patterns that allow for consistent recognition across diverse circumstances. This ability to match what we see with general visual memory patterns serves as an effective mechanism for optimizing brain performance and saving energy. The brain, being naturally against unnecessary effort, constantly seeks to simplify and generalize information to facilitate the cognitive process.