Biology Without Borders


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My research project so far

During the last few months, I’ve been working on a research project in the University of Nottingham. The project consists of analysing data collected by a collaborator from a certain area in Ghana. This area is characterised by a forest-savanna boundary and the datasets contain information on amphibians, birds and plants, including endangered species, and their habitat. However, I was only responsible for analysing the amphibians and plants part, while another student took care of the birds part.

Fruit and seeds of Khaya senegalensis (Credits: Ghana Ecological Research Centre (GEREC), 2014)

Fruit and seeds of Khaya
senegalensis (Credits: Ghana Ecological Research Centre (GEREC), 2014)

After organising all the information in data sheets – so it would be easier, among other things, to see the total amount of species of each group – I was able to load them into the RStudio, a software for statistics analysis and graphics. Therefore, I can find the patterns I am looking for, mainly in climate and habitat-wise.

Hyperolius concolor (Credits: Ghana Ecological Research Centre (GEREC), 2014)

Hyperolius concolor (Credits: Ghana Ecological Research Centre (GEREC), 2014)

Just as the majority of research projects, no one has ever done this type of analysis before, which makes me even more excited about it.

Although there are not any specific results found, this project has given me challenges that will probably help me a lot in the future. One of them was using RStudio. Even though I have used other softwares to analyse data, this one is completely different. Also, developing a research project in a foreign language can be kind of tough but I am sure it will open many doors in the future.

 

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Discovering my work

My research project is based on forest-savannah boundary which is a transition from tropical rain forest to savannah. In this area we can see different distribution of plants and animals species due to the fact that different environments do not host the same species of living beings.

The area of study is in Ghana where my supervisor has a collaborator who has collected data of plants, amphibians and birds. After the field work I am the responsible to analyse the birds data which means I can discover how many birds and how many species of birds exist in each area of the collection, moreover I can see the habitat that birds’ species prefer to live.

rp 1

(Ghana Ecological Research Centre (GEREC), 2014)

The analyse happens because I did an excel table with all information that I have and afterwards I started to use the program RStudio to analyse the table and it is the biggest challenge in my research project because it is my first contact with a computer program. On one hand, I have to dedicate a lot of effort on this and work hardly. On the other hand, I can analyse the data in an easier way once the program help me.

At the moment, I am analysing the data in RStudio and I do not have a concrete result but later I will know more about the fauna in Ghana and see the influence of the habitat in birds’ community.

rp 2

(Ghana Ecological Research Centre (GEREC), 2014)

 

 

Giovana C. M. de Souza


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The Use of Animals in Research

The use of animals in research is a contestable theme because it is usually related with animal suffering. However, the damages are lower nowadays and largely is known in science due to the animals’ usage in the past.

controversy

(Simão-Silva and Rodrigues, 2015)

 

We have a background of animals being studied by humans:

  • Aristotle and Hippocrates dissected animals in ancient Greece and helped medicine to advance;
  • René Descartes assumed that animals were not able to feel pain and they do not have awareness;
  • In 17th century animals were used in a more ethical way;
  • In 1789, Jeremy Bentham affirmed that animals do not have awareness as Descartes had said but they are able to feel pain;
  • The advancement of pharmacology, toxicology and immunology in the 20th century cooperated with animal experimentation. (Baumans, 2005)

You can be wondering the reason of the use animals in research. It happens because human beings and animals have biological systems similar and the knowledge about anatomy and physiology, for example, increase with animal usage in research. Nonetheless, animals cannot be used in any way that researchers want because, in the case of the United Kingdom, since 1986 there is an act which conduct the use of animals in research with the purpose to reduce as much as possible the harm in animals (Festing and Wilkinson, 2007).

Currently, scientists defend the theory of 3Rs to use animals in experimentation (Hills, 2005; Festing and Wilkinson, 2007; Monamy, 2009 and Knight, 2011). This theory is defined by Hills (2005:218) as:

Refinement: the experiment must be designed so that the animals suffers as little as possible.

Reduction: as few animals as possible should be used in the experiment, and the animals used must be of as low psychological development as possible.

Replacement: computer simulations, mathematical model and in vitro experiments must replace experiments on animals wherever possible.

The previous evidences which were given show that animals were and continue being crucial in science although they have been protected by animal rights. We can also consider the social perspective of this subject which I consider the non-scientists’ point of view about the use of animals in research. Usually, non-scientists disagree with animal usage in experimentation and fight for animal rights and welfare what is a respectful action but sometimes they use violence and do not know exactly what is happening inside laboratories which should be following the animal rights once these companies are allowed to do researches with animals.

While the scientific society do not have enough technology to completely replace the animals in experimentation I agree with their usage although the theory of 3Rs should be followed and the animals have to suffer as less as possible.

 

Giovana C. M. de Souza

 

References:

Baumans, V. (2005) Science-based assessment of animal welfare: laboratory animals. Revue scientifique et technique (International Office of Epizootics), 24(2), 503-513.

Festing, S., & Wilkinson, R. (2007). The ethics of animal researchEMBO reports8(6), 526-530.

Hills, A. (2005). Do animals have rights?. Thriplow, Icon

Knight, A. (2011) The costs and benefits of animal experiments. Basingstoke, UK: Palgrave Macmillan.

Monamy, V. (2009) Animal Experimentation, A Guide to the Issues. United Kingdom: Cambridge Uninversity Press

Simão-Silva, D. P., Rodrigues, G. S. (2015) Animais na pesquisa: usar ou não usar, eis a questão. Online at http://etologia-no-dia-a-dia.blogspot.co.uk/2015/02/animais-na-pesquisa-usar-ou-nao-usar.html


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Study reveals chameleons’ colour-changing secret

Swedish researchers recently discovered what many of us have questioned for years: how chameleons change colour. Apparently, this is due to a double layer of special skin cells that changes its structure.

It used to be thought that the ability of changing colours came from dispersing or accumulating pigments inside different skin cells, but this study pointed out what actually happens. Chameleons’ skin cells, iridophores, present crystals in various organisations, shapes and sizes that reorganise themselves when these animals excite or relax their skin, allowing them to change colour. For example, if they see an opponent male, it will affect their skin colour.

Using histology, electron microscopy and photometric videography techniques,  researchers handled nine adults (four females and five males) and four juvenile chameleons of the Furcifer pardalis species, also known as panther chameleons. Besides the two superposed thick layers of iridophore cells, they also discovered that the second layer of cells reflects light and helps these animals to cool their bodies. In this second layer, cells are much bigger and disorganised.

Adult male panther chameleon (Credits: Michel C. Milinkovitch)

Applying RGB (red-green-blue) photometry on high-resolution videos, author Michel Milinkovitch and collaborators could analyse closely how the crystals change inside the skin cells. When the skin is relaxed, iridophore cells are really near each other, so the cells reflect short wavelengths and a colour such as blue is seen. However, when the skin is excited, the crystals get afar from each other, iridophore cells reflect long wavelenghts and colours such as red, yellow and orange are seen. If you’re asking yourself how do we hardly see blue chameleons, the answer should be because their skin has yellow pigments as well, which combined with blue gives us a green colour.

You can watch HERE a video showing a panther chameleon changing colour when exposed to a rival.

Chameleon changing from a relaxed to a excited state, affecting its colours (Credits: Michel Milinkovitch)

The study, published in Nature Communications journal about two weeks ago (10 March, 2015), besides promoting further similar researches, will also provide improvements in other areas, such as engineering, by reproducing the crystals behaviour in new technology.

For extra details, find the original article here.


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Similarity Between the Vision of Primates and Cetaceans

An interesting article about dolphins was published in Nature in January of 2014. Masaki Tomonaga, Yuka Uwano and Toyoshi Saito conducted a research which had the purpose to discover the way that dolphins see the world comparing with the way that humans and chimpanzees do it and because little is known about the vision of dolphins. The reason I have chosen this article is because we can know more about the similarities between mammals even if they live in distinct environments.

Dolphins are able to recognise textures, materials and shapes of object because they use echolocation to know what surround them. However, the aim of the study is to discover more their vision thereby two-dimensional geometric forms with different features were used:

dolphins

(Tomonaga, Uwano and Toyoshi, 2014)

A matching task with these stimuli was made using two-dimensional forms for three dolphins, computer for seven monkeys and visual analogue scaling (VAS) for twenty humans to estimate the similarity between two forms. The results were measured by intraclass correlation coefficient (ICC) which was 0.634 (“substantial”) for dolphins, 0.845 (very high consistency among individuals) for chimpanzees and 0.906 (nearly perfect) for humans. These results show that the vision of the three species is similar with different degrees of vision although the contrasting environments which they live showing the adaptation of mammals under water.

The similarity between the perceptions of dolphins and chimpanzees is r = 0.67, P = 8.81 × 10−6 ; chimpanzees and humans is r = 0.47, P = 0.008 ; and dolphins and humans is r = 0.38, P = 0.021; which is presented as a positive correlation between them. However, this correlation is weaker than the correlation between humans and pigeons which was made in previous study. Nevertheless, the perception of the world by primates and cetaceans is similar.

If you want to read the entire article you can find it here http://www.nature.com/srep/2014/140116/srep03717/full/srep03717.html#ref12.

 

 

Giovana C. M. de Souza