The study of mammals requires you to deal with measurements, which we call numerical â€˜dataâ€™, and you will get practice with compiling and analysing data if you work through all the units in this series. We assume only that you can add, subtract, multiply and divide. In this section, we ask you to use units
Author(s): The Open University

Mammals come in a bewildering variety of shapes and sizes and yet all of the 4700 or so species have some characteristics in common. Indeed, it's the existence of these common features that justifies the inclusion of all such diverse types within the single taxonomic group (or class) called the Mammalia.

This is the first in a series of units about studying mammals. To get the most from these units, you will need access to a copy of The Life of Mammals (2002) by David Attenboroug
Author(s): The Open University

## Question 25

Table 8 shows the atmospheric pressure P in pascals (Pa) at various heights h above the Earth's surface. Plot a graph to give a visual representation of the data in the table. Be careful to label your axes co
Author(s): The Open University

There is a simple feature of uniform velocityâ€“time graphs that will be particularly useful to know about when we come to consider non-uniform motion in the next section. It concerns the relationship between the velocityâ€“time graph and the change in position over a given time interval. Consider the following problem. A vehicle travels at a velocity vxÂ =Â 12Â mÂ sâˆ’1 for 4 s. By how much does its position change over that interval?

Author(s): The Open University

## Video Materials

This extract is taken from S809 Â© 2005 The Open University.

All written material contained within this unit originated at the Open University.

Author(s): The Open University

## Activity 15

Perhaps you are asking yourself why there are so many different imaging modalities. Is there not one that will do everything that is required? The answer, at the moment, is â€˜Noâ€™. With most of the imaging techniques, we cons
Author(s): The Open University

Without a collimator, gamma rays from all directions would be collected by the crystal and no useful image could be obtained. Gamma rays cannot be focused by a lens but a collimator consisting of a series of holes in a lead plate can be used to select the direction of the rays falling on the crystal. Most collimators in use today are parallel hole collimators. A parallel hole collimator is shown schematically in Author(s): The Open University

As the X-rays pass through the patient some of them will be scattered and will therefore not follow the expected line through the patient. If these reach the detector they will blur the image. Some of the scattered radiation can be removed by a grid, usually oscillating, placed between the patient and the detector.

Analogue imaging systems use either film alone (rarely) or a combination of a film and fluorescent material (phosphor). The phosphor fluoresces and produces visible light whi
Author(s): The Open University

The dimensions of the emerging X-ray beam can be altered by the collimator. This helps to ensure that only the region of interest is exposed to the X-rays.

Author(s): The Open University

• Many of the large icy bodies in the outer Solar System are internally differentiated. Thanks largely to tidal heating, some, especially Europa, are likely to have an ocean sandwiched between the icy exterior and the rocky core. Others may have had such an ocean in the past.

• Wherever water rests on warm rock, water must percolate into it and become heated. This will cause hydrothermal convection to begin. Hot, chemical-rich water will emerge
Author(s): The Open University

The weight of evidence in the case of Europa points strongly towards ice overlying salty water, at least within the past few millions years although not necessarily today. There are signs that localised heating episodes have melted and fractured the ice. The intensity of tidal heating has probably waxed and waned in step with fluctuations in the amount of forced eccentricity of Europa's orbit, but we can anticipate that conditions on Europa would have varied through a broadly similar range du
Author(s): The Open University

You might also have noted that there are no obvious impact craters visible in Figure 16 (see Section 2.3.1). In fact there are a few. One is a bright spot, 15 km in diameter, surrounded by a dark halo of ejecta that occurs 10 mm from the top edge and 65 mm from the left-hand edge of the figure. Another is a s
Author(s): The Open University

By the end of this unit you should be able to:

• discuss processes upon and within, and internal structure of, differentiated icy bodies (primarily large satellites) in comparison with the terrestrial planets;

• describe the conditions that may be required to originate and foster life in an icy body and discuss the likelihood of their having occurred;

• recognise the moral and ethical issues of landing spacecraft on potential life-bearing worlds and appre
Author(s): The Open University

The content acknowledged below is Proprietary (see terms and conditions) and is used under licence. This content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 2.0 Licence

Grateful acknowledgement is made to the following sources for permission to reproduce material in this unit:

T
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DA opens the TV programme by stating that â€˜monkeys and apes have the richest social life of all mammalsâ€™. I have explored the importance of colour vision in the interactions between individuals and discussed how gestural and vocal communication add considerably to this richness. But ultimately, it is their ability to be innovative, to discover new ways of obtaining foods, to learn from one another (so-called cultural learning), to form friendships, alliances and coalitions between individ
Author(s): The Open University

In order to be able to state that animals are communicating vocally with one another, scientists need to demonstrate that particular sounds made by one individual can be understood and acted upon by others.

## Activity 5

You will be
Author(s): The Open University

DA stresses that colour vision is very important in primates, not only because colour is used â€˜in sexual displaysâ€™ such as advertising a female's receptiveness to mating [p. 275], but also to identify ripe fruit [p.247] and to select nutritious leaves [p. 255]. This section discusses these points in more detail and explains how the visual system in primates is able to detect colour.

White light is composed of light of different wavelengths, from 300â€“800 nanometres (nm); 1 nm is on
Author(s): The Open University

As you work through this unit you will come across boxes, like this one, which give you advice about the study skills that you will be developing as you progress through the unit. To avoid breaking up the flow of the text, they will usually appear at the start or end of the sections.

In this unit you'
Author(s): The Open University

Durant, J., Bauer, M., Gaskell, G., Midden, C., Liakopoulos, M. and Scholten, L. (2000) â€˜Two cultures of public understanding of science andtechnology in Europeâ€™ in Dierkes, M. and Von Grote, C. (eds) Between Understanding and Trust: the Public, Science and Technology, Amsterdam: Harwood Academic Publishers.
Eurobarometer
Author(s): The Open University