5.5.2 Indris and sifakas Both indris and sifakas are unusual amongst lemurs in that they are active largely by day. Leaves are their primary food. They have a specialised form of locomotion, best described as ‘vertical clinging and leaping’ and the leaps they can take, using their powerful legs, can be up to 10 m. DA describes the bounding movement of sifakas when they are compelled to come to ground. (If you go back to the previous video sequence that shows this strikingly white species – the so-called silky s
5.2 Madagascan diversity Watch the video sequence below, which focuses on just three lemur species – the ring-tailed (in a very brief sequence, leaping from one tree to another), the golden bamboo lemur, already mentioned, and the sifaka, plus the 4 Galagos, lorises and pottos Activity 6 is divided into several parts, on successive pages, and asks you to answer a number of questions. Look ahead to this activity now and highlight, or list, the different ‘process’ words, which tell you what you need to do with the content You should have found ‘describe’, ‘contrast’, ‘eva 8 What makes a successful omnivore? From what has been said already, there's good evidence that the key physical characteristic of the great majority of omnivores is a non-specialist dentition. What about other aspects of their biology? Question: Many omni 3 Is specialisation always advantageous? Specialisation generally implies the possession of adaptations that make animals particularly effective or efficient in one or more aspects of their lives. In many of the examples used in other units in this series, mammals are likely to possess adaptations related to the acquisition and/or processing of food. 10 Living in herds Wildebeest are only one of the species of plant predator that live in herds. Many others do too. Watch the the TV programme from 30.48–47.32 and read LoM p. 109. Identify and write down (a) a couple of advantages and 6.2.4 The speed and direction of the Earth's motion The first significant claim to have detected the motion of the Earth relative to the ‘frame of isotropic 3 K radiation’ came in 1977 from a group at Berkeley, California. They concluded that the Earth is moving at a speed of (390 ± 60) km s−1, in a direction towards the constellation Leo, relative to a frame in which the 3 K radiation is isotropic. Their conclusion resulted from observations of a variation of intensity with angle of the form predicted by Equation 14, which w 5.3 The redshift of the 3 K radiation The temperature, T, of the radiation is proportional to the most probable photon energy, E, which as we have said is proportional to f, and hence inversely proportional to the wavelength λ. Thus, According to Equation 1, we have for the redshift, z 3.3 Extending the distance scale Having reviewed some of the properties of galaxies, we are now in a position to return to the question of how we are to develop further our methods of measuring distance. The various steps taken in determining larger distances from known smaller ones are often called ‘rungs in the distance ladder’. The process of constructing a rung has been: Find a measurable quantity associated with a class of objects. Observe how the measura 3.2 Some general properties of galaxies Firstly, we note that galaxies tend to occur in clusters rather than singly. The mutual gravitational attraction of galaxies naturally tends to hold them on paths that remain close to each other. Typically a cluster contains tens or hundreds of galaxies. There are, however, large clusters with thousands of galaxies, and there are some solitary galaxies. Our own Galaxy is a member of a smallish cluster of about 36 galaxies called the Local Group (see Author(s): 3.1 First steps towards a distance scale As you will see from Table 2, when it comes to astronomy and cosmology, one is called on to deal with a wide range of distances. (Note that a light-year (ly) is the distance light travels in one year, i.e. 9.46 × 1015 m. The distances are also quoted in a very commonly used astronomical unit of distance: the megapar 5.1.4 Getting agreement with the no-monopole law Substituting Equation 7.23 into the no-monopole law gives immediate agreement because The no-monopole law is analogous to Gauss's law in empty space, and it leads to a similar conclusion: the magnetic wave must be transverse. This has already been established using Farada 5.1.2 Getting agreement with Gauss's law Substituting the assumed form of the electric field (Equation 7.20) into the empty-space version of Gauss's law (Equation 7.16) gives The first two partial derivatives are equal to zero because f does not depend on x or y. So we obtain 4.5 Endocrine disruptors Then he was a she… (Lou Reed, American rock singer) In 1996, a book called Our Stolen Future was published, bringing to public attention a debate that had been simmering among biologists for some time. Written by Theo Colborn and two colleagues at the World Wildlife Fund (WWF), this book presented the hypothesis that certain industrial chemicals, commonly found as environmental pol 1.4 Decimal places If you have less than one unit you should put a zero before the decimal point to make it easier for yourself and others to read the value (e.g. you should write 0.4 rather than just .4, as will be explained later in this unit). However, how many zeros should you put after the last whole number in the series? For instance, is 0.4 the same as 0.40? The short answer is that on one level, it is. However, by writing 0.40 we are saying that there are four tenths and zero hundredths, an 1.1 Introducing the decimal system of numbers Many different systems for writing numbers have been developed over the history of humankind. The easiest way of counting small numbers is to use your fingers, and for this reason many numerical systems, such as the decimal system, are based around the number ten. But what happens when you run out of fingers to count on? Numbering systems get round this problem by using a system of scale in which many small units are represented by a single larger unit, and many of these la 5.6 Younger Cover The Younger Cover can be found covering a large part of England, and to a lesser extent, north-east Ireland, south-west Scotland, Arran, Mull, and the north of Skye. From the Ten Mile Maps and Author(s): 5.5 Variscan Orogenic Belt Unlike the Caledonian Orogenic Belt, outcrops of the Variscan Orogenic Belt are limited to the south-west of England, southern Wales and the south of Ireland (see Figure 9 and Author(s): 12.7 Summary of Section 12 For precise localisation of a sound source, binaural cues are required. Two types of binaural cue are used to localise non-continuous sounds in the horizontal plane: interaural time differences, which are most efficient for low-frequency sounds (20–1500 Hz) and interaural intensity cues, which are important for high-frequency sounds (1500–20 000 Hz). The frequency responses in the superior olive reflect these differences. The medial superior olive includes neurons that are responsiv 3.8 Revision questions Discuss the two ways in which the middle ear increases the effectiveness with which sound is transmitted from the external ear to the inner ear.
Activity 7
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Activity 7
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