4.2.4 Science
Although the following examples have been subdivided into broad disciplines of study, you may find it useful to work through all of them, to develop your awareness of what type of information can be defined as common knowledge within science, and what typically needs to be accompanied by a reference.
As in all cases, if you are uncertain whether something within your specific subject area and at your current level of study represents common knowledge or should be referenced, the best option is to include a reference just in case. As you progress with your studies within a particular course, subject area and levels of study, your familiarity of what does and does not represent common knowledge will develop.
A useful basic rule to refer back to is that if the information you want to use can be linked back to a specific person, single group of researchers or specific reference source, and that information is not commonly quoted in textbooks and other literature associated with your study area, then it probably is not common knowledge and should be referenced.
Click on the media player below to listen to Stephen Serjeant, Senior Lecturer in Science, explaining what is regarded as ‘common knowledge’ within Science.
Transcript: Stephen Serjeant, Senior Lecturer in Science
Stephen Serjeant, Senior Lecturer in Science
In general if you’re writing an essay or a scientific report you are claiming to be the originator of that information, either by your own experiments or your own calculations, or your cross comparisons of other results. This is always true unless you say otherwise. And you could do that, for example, by citing the place where you got that information. The only other exception is if you’re saying something that is so well known that it’s obvious to every reader that you’re not the originator of this result, and this is what I think is meant by common knowledge. So, for example, ‘that the Universe is expanding’ – if you say that in a piece of academic writing, people aren’t going to assume that you are the discoverer of that because that’s well known, that’s someone else. I think this is very similar across disciplines. Science is not particularly unusual here.
The key test whether something is or isn’t common knowledge is whether a reader might think from reading your report that you have generated this information from your own experiments or your own calculations. Remember, this is the default assumption for anything you’re writing. For example, if you take a diagram from the web and stick it in your essay or report, and you don’t say where you got it from it’s going to look very like you made it yourself – okay? And, so, not saying where you got it, is regarded as a sort of fraud, scientific fraud, and this is taken very seriously. Also taking a direct quote from someone else and not putting it in inverted commas is a way of passing those words off as your own words and that’s a similar sort of fraud. It’s all plagiarism.
But if you want to quote a number of key points from some well researched or well understood area, it’s okay to cite a textbook or review article for all of these results provided that it’s clear from your phrasing that your citation refers to all of these points. Alternatively, you could hunt down the original references such as Edwin Hubble’s original discovery of the expansion of the Universe, but only do that if you’ve read them because you may be surprised at the content.
Academic judgement is an assessment of your readership. Are your readers likely to believe that because you say, for example, ‘humans evolved from other primates’, that you’re claiming to be the one who’s found that out? Well, maybe not in that case, but if there’s any danger that they might make that assumption about anything else that you’ve got from elsewhere then cite your source. Is it better when in doubt to reference? Absolutely. Yes.
4.2.4.1 Health Sciences
Example 1
There are two types of diabetes. Type 1 diabetes is caused by the body not producing any insulin, whereas Type 2 diabetes is caused by the body not producing enough insulin to ensure blood sugar levels are controlled effectively.
Is this common knowledge or does it need to be referenced?
Answer
This is an example of common knowledge. It is something you may already know or could easily find stated in a wide range of source materials and academic dictionaries, without being accompanied by a reference.
Example 2
Type 2 diabetes is the most common form of this condition and is commonly linked to obesity. In 2007, 2.5 million people had been diagnosed with Type 2 diabetes across the UK (equal to 3.66% of the population), with this estimated to increase 160% to ~4% by 2025.
Is this common knowledge or does it need to be referenced?
Answer
This statement starts off with a general statement about the link between obesity and Type 2 diabetes, which is common knowledge and does not need to be referenced. In contrast, the second sentence contains some very specific information, the exact details of which are unlikely to be widely known and need to be shown to have come from a reputable source. As such this sentence should be accompanied by a reference.
In this case, this information was extracted from www.diabetes.org.uk/ Documents/ Reports/ Silent_assassin_press_report.pdf [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] (last accessed on 30 Oct 2008). The correct way to show this statement in an answer would therefore be:
- Type 2 diabetes is the most common form of this condition and is commonly linked to obesity. In 2007, 2.5 million people had been diagnosed with Type 2 diabetes across the UK (equal to 3.66% of the population), with this estimated to increase 160% to ~4% by 2025 (Smallwood, 2008).
At the end of the piece of work, depending upon the style of referencing you were using, you would give the full reference as:
- Smallwood, D. (2008) ‘Diabetes: beware the silent assassin’, London, Diabetes UK; also available online at www.diabetes.org.uk/ Documents/ Reports/ Silent_assassin_press_report.pdf (Accessed 30 October 2008).
4.2.4.2 Molecular Science
Example 1
Analytical tests on samples of Greco-Roman cosmetic powders have revealed that the pink coloration can primarily be attributed to various compounds originally extracted from madder plants.
Is this common knowledge or does it need to be referenced?
Answer
This statement relates to a specialised subject and area of study (not everyone is involved in analysing the chemical composition of archaeological cosmetics) and is unlikely to be widely known, even within the chemistry community. In addition, there is the implication that this information has been obtained from a specific source (e.g. the specific study on these samples), and as such, it should be accompanied by a reference.
The correct way to show this statement in an answer would therefore be:
- Analytical tests on samples of Greco-Roman cosmetic powders have revealed that the pink coloration can primarily be attributed to various compounds originally extracted from madder plants(1).
With the full reference listed at the end of the work, e.g.
- (1)Van Elslande, E., Guérineau, V., Thirioux, V., Richard, G., Richardin, P., Laprévote, O., Hussler, G. and Walter, P. (2008)‘Analysis of ancient Greco-Roman cosmetic materials using laser desorption ionization and electrospray ionization mass spectrometry’,Analytical and Bioanalytical Chemistry,vol. 390, no. 7, pp. 1873–79.
Example 2
Lewis structures are used to represent the bonding relationships between atoms within any covalently bonded molecule, and indicate how lone pairs of electrons are shared in accordance with the octet rule.
Is this common knowledge or does it need to be referenced?
Answer
This statement contains a number of scientific terms that are likely to be unfamiliar to anyone who has not studied chemistry. In contrast, this method of depicting molecular structures is commonly used at all levels within chemistry, would be found unreferenced in any academic textbook or source material, and so represents common knowledge within this discipline. As such it does not need to be referenced.
4.2.4.3 Geosciences (Earth and Environmental Science)
Example 1
The island of Réunion located in the southwest Indian Ocean is an intra-oceanic plate shield volcano consisting of two coalesced volcanoes – Piton des Neiges (dormant) and Piton de la Fournaise (still active). The island is characterised by ultramafic to mafic alkaline eruptive sequences, typical of ‘hot spot’ volcanic sequences.
Is this common knowledge or does it need to be referenced?
Answer
The information cited in this statement could be obtained from a number of different sources, with the second sentence linking commonly known information (within the discipline of Earth Sciences) about hot spot volcanoes to this specific example of the island of Réunion. As such, this statement can be viewed as common knowledge and does not require a reference.
If the statement went on to describe the range of rock types found across the island (e.g. picrites and oceanites, overlain by more evolved hawaiites, mugearites and benmoreites, which in turn are overlain by more evolved trachytes), then this level of detail should be backed up by an appropriate reference (e.g. Upton, B.G.J. and Wadsworth, W.J. (1972) ‘Aspects of magmatic evolution of Reunion Island’, Phil. Trans. R. Soc. London, 271, pp. 105–130).
Example 2
Darcy’s law is a measure of the rate of flow of a fluid through a porous substance. It states that the flow velocity (
measured in m s–1) through a porous substrate is proportional to the difference in height in metres (Δh) divided by the distance (Δl) down a slope between two points, multiplied by the hydraulic conductivity of the soil (K), which is a constant, i.e.
As the flow velocity () is proportional to the hydraulic gradient (Δh/Δl), an increase in the gradient will result in a predictable and fixed rate increase in the flow velocity.
Is this common knowledge or does it need to be referenced?
Answer
Although the topic of this statement is relatively complex, for any student studying Level 2 (or higher) Environmental Science, Darcy’s law and its usage would represent common knowledge, and could be found in any number of relevant academic textbooks or reference sources. As such, stating this law or what it is commonly used for would not require a reference within an Environmental Science answer.
If, however, you cited a specific example of the use of Darcy’s law using data that you did not collect yourself, then this should be accompanied by a reference to indicate the source of this specific information.
4.2.4.4 Physical Science
Example 1
Newton’s third law of motion states that when an object exerts a force on another object, the second object will exert a force of the same magnitude in the opposite direction on the first object. This is commonly simplified as: for every action there is an equal and opposite reaction.
Is this common knowledge or does it need to be referenced?
Answer
Newton’s laws of motions are commonly known and used throughout science at all levels of studies, and can be found described in a very large range of academic reference sources and textbooks. As such there is no need to include a reference for this type of widely known and widely used information.
Example 2
The radio galaxy Cygnus A has been found to contain a central dust lane and clear ‘opening cone morphology’, both of which have been attributed to star formation commencing
Is this common knowledge or does it need to be referenced?
Answer
This statement is based on specific research work carried out by a group ofManchester astronomers, published in the Monthly Notices of the Royal Astronomical Society. Although the statement has been rewritten from the original, and summarises some of the key outcomes of this work, acknowledgement needs to be made to the original source, to verify where this detailed information was obtained from.
The correct way to show this statement in an answer would therefore be:
- The radio galaxy Cygnus A has been found to contain a central dust lane and clear ‘opening cone morphology’, both of which have been attributed to star formation commencing
With the full reference listed at the end of the work, e.g.
- Jackson, N., Tadhunter, C. and Sparks, W.B. (2002) ‘Cynus A: stars, dust and cones’, Monthly Noticesof the Royal Astronomical Society, vol. 301, no. 1, pp. 131–141.