Deep sea organism analysis

[mollykins]

I'm doing my biology c/w on the difficulties of studying marine life that live in deep water.

I'll write about how even if you build expensive submarines etc you can't observe them properly as you'r noise and light is a distraction, so specimens have to be taken (and possible impacts) and then i want to write about tests biologists do on these animals (preferably larger animals rather than stuff like plankton.) But apart from dissecting their stomachs to find what they eat i don't know many of the processes very well.

For example does anyone know (or know of a book/ website) where I can get RELIABLE info about how they analyse the DNA and do other such tests? i don't want to google it and click on the first thing i see which could be totally wrong.

[society]

I have a question for you Jomifl - what do you do, what is your background? I've mentioned before to you how knowledgeable I find you to be, and I always read your posts. :-)

[society]

Btw, good going Molly.

[jomifl]

Hi Society.. My experience is in coastal marine and freshwater biology, more on the practical than the academic side. I am now retired and living in France. What knowledge I have is general and not very specialized and was gleaned from an interest in natural phenomena.

[society]

Thank you Jomifl. :-)

[jomifl]

De rien ..society ;-)

[mollykins]

Wow I never knew that Jom, BTW I did tweak the letter slightly, after having a biology lesson on Thursday. The teacher suggested I focused on one kind of analysis so that i could get the scientific detail i needed, so chose DNA analysis and what scientists can tell about a creature from it. But My teacher did say that if I ended up with not enough words (whole thing should only be 2000 in total) that i could do something else such as carbon dating to find out how old the specimen is.

[jomifl]

Molly if it is old enough to do carbon dating on then it is almost certainly dead. In practice all scientists are specialists so will only study one or two aspects of a subject. The point I didn't make clear earlier is that what a scientist wants to do is to answer some sort of question such as how long does something live or what does it eat or how does it catch its prey. These questions can be answered either by direct observation of behaviour or by measurement of some parameter or by analysis. DNA analysis is used for population dynamics but it is not the only method available and not always applicable. For example if you catch a sample of fish and measure them you will find that they will fall into different size groups. Each size group will represent the product of a spawning period (usually yearly in non tropical waters) so that the largest and oldest group will be the smallest in number ( due to natural loss through predation and disease) From this you can calculate the average age of the fish and extrapolate to find out how long they might live. From this you can calculate how many fish can be caught every year without destroying the population.( if that was the question that initiated the study. This completely ignores what the fish eat, whether they migrate, where and how they spawn and what interactions they have with other species. You would need another question to study these. Hope this helps

[whiskeryron]

I hope you get an early reply mollykins & good luck with all your studies. Ron.