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4.3 The European Commission

The European Commission is the political body that represents the EU as a whole. It is politically independent and can propose legislation, policies and programmes of action. It is also responsible for implementing the decisions of the European Parliament and the Council of the European Union.

The European Commission is made up of a team of Commissioners (appointed by EU member states) and their support staff. Commissioners are chosen ‘on the grounds of their general competence’ and
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3.5 Inheritance

The adaptive explanation for bright coloration in male guppies given above can only be correct, and can only have evolved by natural selection, if male coloration has a heritable basis. Direct evidence that it is a heritable character is of two kinds. First, a wide variety of decorative guppies have been bred for sale on the aquarium market. Such forms could not have been produced if male coloration were not heritable. Second, if samples of guppies are taken from different Trinidadian streams
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3.4 Variation

Guppies vary in a number of characters; in particular, male guppies vary in the number, size and brightness of the coloured spots that decorate their bodies (Figure 2). This variation can be detected within a single population in a given stretch of stream, but is much more obvious when different populations, from different
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3.2 Number of progeny

Female guppies begin to breed as soon as they become mature at about three months old; they then produce clutches of eggs, most of which become fertilized, at roughly one-month intervals until they die or become too old. Clutches vary in size from one to 40 eggs; the average clutch contains about 10 eggs. Thus, female guppies produce a large number of offspring during their lives, far more than can survive to maturity.

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3.1 Introduction

The purpose of this section is to consolidate your understanding of the theory of evolution through natural selection by looking at a specific example. The guppy (Poecilia reticulata) is a small fish whose natural habitat is small streams in northern Trinidad, but it is also a popular aquarium fish. Male and female guppies are very different in appearance (Author(s): The Open University

Learning outcomes

At the end of this unit you should know that:

  • By biological evolution we mean that many of the organisms that inhabit the Earth today are different from those that inhabited it in the past.

  • Natural selection is one of several processes that can bring about evolution, although it can also promote stability rather than change.

  • The four propositions underlying Darwin's theory of evolution through natural selection are: (1) more individuals are produced
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Introduction

In this unit, we describe the theory of evolution by natural selection as proposed by Charles Darwin in his book, first published in 1859, On The Origin of Species by Means of Natural Selection, or The Preservation of Favoured Races in the Struggle for Life. We will look at natural selection as Darwin did, taking inheritance for granted, but ignoring the mechanisms underlying it.

This unit is from our archive and is an adapted extracted from Discovering science (S103) whic
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Acknowledgements

Unit Image

Courtesy of banlon  1964:

All other materials included in this unit are derived from content originated at the Open University.


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1.6.6 Professional bodies and societies

Consider joining a learned society or professional organisation. They can be very useful for conference bulletins as well as in-house publications, often included in the subscription. Don't forget to ask about student rates. Try looking for the websites of learned societies associated with your subject area (e.g. The Royal Society, the Institute of Electrical
Author(s): The Open University

1.6.5 RSS

RSS (‘Really Simple Syndication’ or ‘Rich Site Summary’) newsfeeds supply headlines, links, and article summaries from various websites. By using RSS ‘feedreader’ software you can gather together a range of feeds and read them in one place: they come to you, rather than you having to go out and look for breaking news. The range of RSS feeds on offer is growing daily. There is probably a feed to cover all aspects of your life where you might need the latest information, and you may
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1.6.3 Mailing lists and newsgroups

Mailing or discussion lists are e-mail based discussion groups. When you send an e-mail to a mailing list address, it is sent automatically to all the other members of the list.

The majority of academic-related mailing lists in the UK are maintained by JISCMail  You will find details of joining these mailing lists on the JISCMail website. Mailing lists are useful for getting in touch w
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1.6.2 Alerts

Online bookshops and some of the major search engines offer ‘Alerts’ services. These work by allowing you to set up a profile once you have registered on their site, and when there are items meeting your criteria you receive an email. The good thing about alerts is that you don’t have to do anything once you have set up your profile. The downside, particularly with alerts services from the search engines, is that given the extent to which internet traffic is on the increase whether new
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1.6.1 Introduction

The process of keeping up-to-date in your chosen subject area is useful for your studies and afterwards, for your own personal satisfaction, or perhaps in your career as part of your continuing professional development.

There are a great many tools available that make it quite easy to keep yourself up to date. You can set them up so that the information comes to you, rather than you having to go out on the web looking for it. Over the next few pages, you will be experimenting with some
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1.5.9 Plagiarism

Referencing is not only useful as a way of sharing information, but also as a means of ensuring that due credit is given to other people’s work. In the electronic information age, it is easy to copy and paste from journal articles and web pages into your own work. But if you do use someone else’s work, you should acknowledge the source by giving a correct reference.

Taking someone's work and not indicating where you took it from is termed plagiarism and is regarded as an infringemen
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1.5.7 Referencing

We mentioned above that we need to reference sources to ensure we abide by copyright legislation. But there is another reason we need to give accurate references to items we use – so we can share it.

Consider this scenario. A friend says they’ve just read an interesting article where Joshua Schachter, founder of Delicious has spoken about why it isn’t a faceted search system, and you should read it. How would you go about finding it? Would you start looking in a news database, a s
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1.5.6 Copyright - what you need to know

An original piece of work, whether it is text, music, pictures, sound recordings, web pages, etc., is protected by copyright law and may often have an accompanying symbol (©) and/or legal statement.. In the UK it is the Copyright, Designs and Patents Act 1988 which regulates this.

In most circumstances, works protected by copyright can be used in whole or in part only with the permission of the owner. In some cases this permission results in a fee.

However, the UK legislation inc
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1.5.5 Social Bookmarks

If you find you have a long unmanageable list of favourites/bookmarks you might like to try social bookmarks as an alternative.

Activity - What you need to know about Social Bookmarks

Read 7 things you should know about social
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1.5.4 The 5 Ds

If you don’t use a system at all, then you could suffer from the effects of information overload:

  • losing important information

  • wasting time on trying to find things

  • ending up with piles of physical and virtual stuff everywhere

One technique you might like to apply to your files (be they paper or electronic) is the 5Ds. Try applying these and see if you can reduce your information overload.


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1.5.3 Desktop search tools

Finding your paperwork or electronic files can be a problem. You may find that even if you do have some sort of filing system, your structure soon gets quite large with files in multiple locations, which can be hard to navigate. You may find yourself making arbitrary decisions about which folder to place a document in. It may make sense now but in the future, when you look where you think it should be, it’s not there.

At times like this you may resort to the search command from the Wi
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1.5.1 Why is it important to be organised?

  • 87% of items that are filed into a filing cabinet are never looked at again. STANFORD UNIVERSITY

  • In 2010, the world’s digital information output was estimated to pass 1.2 zettabytes. A zettabyte is a new term which equals a thousand billion gigabytes.

  • A new blog is created every second. TECHNORATI

  • 10% of salary costs are wasted as employees search for information to complete tasks.
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