Biology Without Borders


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The arguable cloning process

Since Dolly the sheep, cloning has always been a controversial topic and discussions on the use of clones for food and genetically modified animals are frequent.

Dolly, the sheep, first mammal cloned from an adult cell (Credits: BBC News UK)

Dolly, the sheep, first mammal cloned from an adult cell (Credits: BBC UK News)

Cloning is the process of creating new organisms that are exact genetic copies from a single “parent” organism. Although geneticists have said that it is basically “an extension of the process by which twins arise in nature” and consequently there’s no need to worry about its safety in terms of food or modified organisms, cloned animals can face many problems. These problems may include obesity, seizures, tumors, severe cardiovascular problems, thymus problems and joint problems.

Also, there is a good amount of groups that oppose the use of food genetically modified, including Center for Food Safety, Consumers Union and Humane Society of the United States. Besides that, it can cause unnecessary suffering to the animals involved.

On the other hand, science has shown promising results when it comes to clones created to help humans prevent diseases. Researchers in Texas A&M University have already created this type of animals in collaboration with a company called rEVO Biologics. However, since cloning is such a tough task, experimental and requires not only skill but also luck, it’s easy to say that the benefits of this artificial process are still questionable and not satisfactory.

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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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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.