Manny and Sid Reunion?

Many tens of thousands of years ago, the tundra landscape of Northern Eurasia and America was significantly different. It was part of a high pressure system, giving a more temperate climate, leading to a greater biodiversity than the present day. The picture would typically be of herds of woolly rhinoceroses, bison and wild horses grazing on shrubs and herbaceous plants. However, the dominant animal here was the massive woolly mammoth. These impressive mammals grew up to 3.4 metres tall and weighed in at perhaps as much as 6 tonnes. The most striking feature of these animals was their huge tusks, some as long as 4.2 metres.

The reason these animals hold the public imagination (more so than other remarkable creatures, such as the giant sloth) is that many specimens have been immaculately preserved in ice. This is also why the mammoth is one of only two extinct organisms to have had its DNA sequenced (the other being Neanderthals). This sequencing has opened many intriguing possibilities.

Firstly, the DNA of the mammoth had to be extracted. This stage was done using 20 balls of hair found frozen in Siberian permafrost. The hair was more advantageous to use than bones for two reasons: less contamination because the keratin (the protein found in hair and nails) protected the DNA, and the DNA was more easily removed.

Next the DNA was sequenced. Essentially DNA is the genetic code for all organisms. It consists of ‘bases’, of which there are four, called A, T, C and G. Previously, mammoth DNA had only been sequenced from the mitochondria in the cell (only 13 of the 20,000 genes are here). However this experiment studied the nuclear DNA, which codes for the actual physical characteristics of the mammoth. The research was carried out by biologists at Penn State University.

The results of the experiment yielded many interesting observations. The first was that the mammoth population split into two different sub-populations around 2 million years ago. One of these populations went extinct 45,000 years ago, whereas the other about 10,000 years ago. The data also showed that mammoths had a low genetic diversity, which meant that they were much more susceptible to a particular disease, which is a possible cause of extinction. Perhaps we owe the cavemen a sincere apology for blaming them?

The question most will now be asking themselves is evident: using this data, is there the possibility of bringing the mammoth back to life? The answer, in short, is yes, but there are obvious stumbling blocks. There are two feasible methods which would allow for the recreation of the species.

One method would involve taking an elephant egg cell, removing the genetic material and replacing it with the nucleus from mammoth tissue. This fertilised egg (or zygote) would then be inserted back into a female elephant, and the calf would be a clone of the mammoth whose DNA was used. This method is virtually identical to that used to create Dolly the sheep in 1996. The method is known to work, since it was employed in 2011 when the first ever extinct animal, the Pyrenean Ibex, was brought ‘back to life’. However, the new-born kid (baby goat) only survived for seven minutes after birth due to lung defects. This is a reminder of the difficulties faced in cloning complex animals. It took 277 attempts to make Dolly.

The second method would involve the artificial insemination of an elephant egg cell with the sperm cell from a frozen mammoth. The offspring would be a hybrid of an elephant and a mammoth (perhaps a mammophant?!) but after successive cross-breeding of the hybrids, an almost pure mammoth would result. A problem with this method is that sperm cells of living mammals are potent for 15 years at most after deep-freezing.

Despite the difficulties, a team of Japanese, Russian and U.S scientists have aimed to create a mammoth within 6 years, using the first method (using the information from the DNA sequencing). Questions have been raised as to how ethical the result would be: mammoth were very sociable animals and may not be happy without a herd. Secondly, the mammoth’s habitat is much colder now (unfortunately for 20th Century Fox, Manny and Sid from the Ice Age films may never have seen snow). Some people have, therefore, argued that it would be a better use of money to protect the endangered elephants of Africa.

To conclude, the idea of recreating the mammoth is fraught with ethical and technical difficulties, but may provide one of the most testing yet satisfying challenges in modern biology. I suppose in the end, all we really know is that if you cross-bred a mammoth with a kangaroo, you would end up with huge holes in the ice (!)

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Uneducated Genius’s

Was thinking, and I thought why is it that so many people that have made HUGE discoveries in biology don’t have any formal training in the subject?? 

A few examples I can think of are:

  • Charles Darwin (studied divinity at university)
  • Gregor Mendel (was an abbot at a monastery in the Czech Republic)
  • Alfred Russel Wallace (was too poor to afford an education)
  • Carl Linnaeus (who came up with many of his classification ideas from his expedition)

I suppose it goes to show you only need a brain to succeed, and you shouldn’t mix intelligence with education 😉

“The culling of…

“The culling of badgers is absolutely obscene. The largest ever study found that it would make things things worse not better, yet they still push ahead towards the meaningless destruction of our wildlife”

Wendy Turner Webster said this AND SHE IS NEVER WRONG.

I don’t know if the badger cull is a good or bad thing HELP

Badger Cull Ambivalence :O

Usually if something like this happens, I am screaming OH MY GOSH THEY’RE KILLING THOUSANDS OF INNOCENT CREATURES HOW CAN THEY THEY ARE POOPY PEOPLE!!

Buuuuuut, I can sort of see where they are coming from…. 

If it makes the badgers healthier, and the cattle at a lesser risk of contracting TB then It must be good? Apparently they have to be shot humanely and it’s only a trial.

I shouldn’t want it, or should I :O

All I know is I couldn’t kill a lickle badger wadger 😦

Variation in biology

Just a quick post on my thoughts about evolution by natural selection……

I think evolution is an incredibly amazing idea courtesy of Charles Darwin and Alfred Russel Wallace, and makes our lives so incredibly fulfilled through the knowledge of how we got here.

My one confusion is how the variation occurs. I think it is kind of a paradox how one species, say a platypus, would always give birth to the same species, i.e. another platypus, and so then this species would give birth to another and another and another and so on. In this way an evolutionary chain is set up whereby all the generations should be the same species, but they aren’t, obviously since we have so many life forms from a single cell billions of years ago.

I find it hard to understand this, but I suppose if you think of it as gradual changes over a huge period of time, then the ‘species’ will change so much from its ancestors that it could not longer interbreed with them to create fertile offspring, if they were both alive at the same time.

Feel free to write your own comments about evolution, I would be very interested 🙂

Nature vs. Nurture

This  debate has been going on for ages so I thought I would say what I think on the matter 🙂

In my opinion, there can be no doubt that the phenotype, or characteristics of an organism are due to an interaction between genes and the environment. In my mind, the debate should be centered on what extent the genes or environment play in the development of an individual.

Everyone knows that some people are exceptionally musical, and can hear a piece of music, for example, and play it back on the piano, or whatever instrument they excel at. However, say  someone had never encountered a musical instrument before. For example, a child living in a remote part of the Amazon. This child could have a genetic inclination towards playing an instrument, but without the tools, i.e. without the correct environment, this characteristic is not shown, and the child could be fairly average in every other aspect of character.

This idea can be applied to nearly every other subject: how can a maths genius be a maths genius without knowledge of numbers; how can someone adept at languages be a ‘language genius’ if they are not taught any language; how can someone who is ‘born to perform’ be a confident performer if they are never put onto a stage?

However, I think the basis of an individual’s characteristics are most definitely their genes. One cannot dispute that an incredibly clever husband and wife who have children will not have ‘clever children’ with similar IQs, unless a severe change in the environment changes this.

It is quite interesting to look at the correlation coefficients for IQs in different children, i.e. twins who were separated at birth and raised in different environments, or adopted children. This website shows this information quite well:

http://en.wikipedia.org/wiki/Nature_versus_nurture#IQ_debate

NB: 

  • Correlation coefficient of 1 means a strong positive correlation
  • Correlation coefficient of 0 means no correlation
  • Correlation coefficient of -1 means strong negative correlation

I also believe that everything everybody has the ability to change what their genetic path, or environmental inclination may be, so long as they have the tenacity to succeed in what they want to do 😀