This is my first time posting here, so please forgive the breaches of etiquette. I have wandered around here a bit to get a feel and I see my questions are going to seem naive but I must ask anyway.

The behavior known as instinct raises some sharp questions in my mind. To set things up a bit I'll mention that salmon navigate some very complex physical environments in a very precise way (relative to most things). The Arctic Tern migrates 24,000 miles each year.

First, am I correct in assuming this migratory behavior by both species is in fact instinct?

If it is instinct, then is instinct manifested as a pre-existing memory, sort of like a hard-wired neural configuration that is essentially indistinguishable from a trained set of pathways?

The only other thing that I can think of as an alternative to the above is if migratory instinct was manifested as a kind of map, or a series of markers, or a specific flight plan with course and range at some fairly detailed level.

In any case, both of these scenarios somehow imply that the instinct, in whatever manifestation, is coded for in DNA. So the question becomes: how the hell did DNA take on knowledge of the external, physical world? Could there be a recorder gene that somehow transcribes base pairs using some scheme that is altered by movement? That seems far-fetched to me but then the question still remains: how did the instinct get coded for?

There seem to be hints that say I'm reading into this far to deep and that it must be a simple mechanism. The reason I say this is because if it is a complex process then it begs the question: why the hell go through so much complex stuff and why burn so much energy to complete a task that so many other species seem to successfully ignore? These are two succesful species that would seem to be pressured in the wrong direction for survival.

Welcome, Kackerman

Enjoy your visits!

I have no knowledge on Avian migration I'm afraid, but the site below seems to lean toward instinct as far as I can tell.

elibrary.unm.edu/sora/Auk/v025n03/p0329-p0333.pdf

It is dated 1908, but is at least available for reading on the web, unlike more recent publications which Google finds (unless you fork out for registration).
I'll have a deeper look soon as I can becasue it is an interesting topic and quite close to the nature - nurture discussions which affect mankind.

PS - here's another site http://en.wikipedia.org/wiki/Bird_migration
and another http://www.scq.ubc.ca/?p=173

Hi kackermann, glad to see you joined

I reponded to your post in another forum as well, & made reference to a book on the topic.

Enjoy!

I have PM'd you to give the location of a ppt lecture on animal migration. Basically, the answer to your question is that there are (i) innate (genetically programmed) mechanisms (of physiology, biochemistry, anatomy etc) that are available and then (ii) learning experiences (from parents, peers, simple trial and error etc) that modify/compliment them. However, there are very many variations. For example, the shining cuckoo has been shown to migrate correctly over 400 km even though individuals have been isolated from other cuckoos. Thus , this is assumed to be entiely due to innate mechanisms using some form of compass and a knowledge of where its location origin is.

Hello.

My first rambling:

The innate /genetically programmed) mechanisms/tool mostly referred to is the inbuilt compass. Wich infact is very small magnets in the body/brain that lets the bird relate to the earths magnetic field.

news.bbc.co.uk/2/hi/science/nature/3629775.stm

But it also navigate using other "clues" in nature as you may read in above link, so it has a pretty complex input from the environment.

Migrating birds are not the only life form with thees inbuilt magnets:
sciencedaily#com/releases/2007/07/070705101457.htm
Chickens have them.

And even some bacteria:
physorg#com/news8344.html

I remember reading somewhere that human ancestors at sometime took use of this tool to, and that humans still have traces of thees minerals in our brain, but not sure if it's just a myth or not.

Interesting links. The bacteria use magnetic iron mineral magnetite (Fe3O4), which is unlikely to be in human brains though iron, zinc, and other metals are present in abundance.