Fish preserve DNA 'memories' far better than humans do

[txchaser]

Ok so this sounds like silly angler tales, but it's legit. Published in Nature (reputable in science-land) and verified by an independent group too. It's not really memory, but it does say "it seems possible they can transmit life experience through their DNA in the form of methylation."

 

https://www.sciencedaily.com/releases/2019/08/190808091403.htm

 

 

Date: August 8, 2019

Source: University of Otago

 

We are all familiar with the common myth that fish have poor memory, but it turns that their DNA has the capacity to hold much more memory than that of humans. Researchers report that memory in the form of 'DNA methylation' is preserved between generations of fish, in contrast to humans where this is almost entirely erased.

 

In a study published recently in the journal Nature, University of Otago researchers report that memory in the form of 'DNA methylation' is preserved between generations of fish, in contrast to humans where this is almost entirely erased.

 

DNA is often compared to a large book, with the words representing an instruction manual for life. DNA methylation encodes additional information that we are only starting to understand -- a little like discovering handwritten notes in the margins of the book saying which pages are the most important, or recording newly acquired information. In humans, these notes are removed at each generation but this apparently does not occur in fish.

 

First author of the study, University of Otago Anatomy PhD student Oscar Ortega elaborates; "Methylation sits on top of DNA and is used to control which genes are turned on and off. It also helps to define cellular identity and function. In humans and other mammals, DNA methylation is erased at each generation; however, we found that global erasure of DNA methylation memory does not occur at all in the fish we studied."

 

In recent years much attention has been paid to the idea that significant events such as war or famine can have a lasting effect on subsequent generations through the inheritance of altered DNA methylation patterns. While these 'transgenerational' DNA memory effects appear to be potentially important, because of DNA methylation erasure events during development, it is thought to be extremely rare in humans. However, because fish apparently do not have these erasure events, it seems possible they can transmit life experience through their DNA in the form of methylation.

 

Dr Tim Hore, research team leader and Senior Lecturer, at Otago's Department of Anatomy, says the study's findings provide new avenues for scientists to study how the memory of events in one generation, can be passed on to the next.

 

"Mammalian biologists have searched long and hard to find reliable examples of where altered DNA methylation patterns are passed on to subsequent generations; yet only a handful have been verified in repeated studies. However, unlike humans, DNA methylation is not erased at each generation in at least some fish. So, we think intergenerational memory transfer through DNA methylation could be much more common in fish," Dr Hore says.

 

Also published in Nature Communications is a complementary study from the Garvin Institute (Australia), confirming the Otago observations. "It is really great to have immediate validation that our results are robust -- they used different techniques and developmental samples, but came to the same conclusions as we did," Dr Hore adds.

 

The researchers hope this new knowledge into DNA methylation inheritance will drive new understanding into what molecular secrets are passed from parents to their offspring, ultimately, rewriting the book of life as we know it.

 

[Wizzlebiz]

This doesnt suprise me at all. DNA is capable of storing crazy amounts of memory.  

 

I have always considered the meaning of life to be the acquisition of information.  Gathering info to pass down to future generations.  We can tell tales of things once was. 

 

Fish cannot talk so this is there passing tales so to speak. 

[Paul Roberts]

Interesting. Not sure what it means. But I can certainly speculate.

 

An example might be fish learning to avoid lures. It's already known that fish do learn to avoid certain lures. And every fish doesn't have to be stuck by it either. They appear to learn by observing other fish.

 

Now... it could be that such info might be able to be passed on to future generations, without selective culling; That is, removing fish from the population once it's been caught, leaving only "naive" fish in the population. This has long been a practice in English trout streams, where trout caught are killed so that they don't become too difficult to catch. This finding does make one wonder about the extent to which segments of fish populations could learn to avoid lures.

 

Interesting that brown trout as a species -the trout of those English trout streams- have been angled for a LOT longer than our American salmonids have. And, they of all trout, have the well-deserved reputation as the most difficult of trout to dupe on flies. From my time working in a trout hatchery, I came to know browns as having other deep-seated behavioral habits that also contribute to their apparent aversion to angling. I'd always wondered about this.

 

This finding could also be in the running for explaining how it is that certain hot lures go gangbusters when first introduced to naive fish. Only to wind up in the dark corners of our tackle boxes, so many years later.

 

Thanks for posting this @txchaser.

[senile1]

@Paul Roberts, your take on the original post is similar to mine.  Thanks for the additional interesting info on brown trout as well.  ?

[CrankFate]

I guess the people that inherit this are the ones who can remember their past lives.....

[TheRodFather]

Yesss!  Scientific proof I can lean on when I get skunked!

 

There is compelling evidence that catch and release teaches the fish and we are shooting ourselves in the foot by releasing.

[schplurg]

On 10/27/2019 at 5:27 PM, TheRodFather said:

Yesss!  Scientific proof I can lean on when I get skunked!

 

There is compelling evidence that catch and release teaches the fish and we are shooting ourselves in the foot by releasing.

 

 

It's just a study.

 

As for the trout example above, couldn't the opposite be true? That all of the smarter fish never got caught and that by eliminating the ones that do get caught (the dumb ones) you are actually leaving the smarter fish to breed and make more smart ones?

 

It's a much simpler explanation.

[TheRodFather]

On 11/1/2019 at 12:41 PM, schplurg said:

 

 

It's just a study.

 

As for the trout example above, couldn't the opposite be true? That all of the smarter fish never got caught and that by eliminating the ones that do get caught (the dumb ones) you are actually leaving the smarter fish to breed and make more smart ones?

 

It's a much simpler explanation.

I would think they all fell for a lure or bait once.  Some learned, some didn't, just like people.

 

(I like having an excuse for getting skunked, so I'm going with that :))

[Luke Barnes]

I'm understanding this as, the fish being caught and having a form of PTSD from it. It was traumatic for the fish to think it's getting a meal then suddenly jerked out of the water. So that imprints onto the fishes DNA and subsequent offspring are born with it and are perhaps more skittish. Less likely to take a lure and overall harder to catch. 

 

That sucks!!! That's why farm ponds that have never been fished are so amazing I guess, I've never fished one, so again speculation. 

[Fishingmickey]

I think it is like this, Some bass are glutinous pigs and will eat anything that even resembles food. Heck they think they can spit it out if they don't like it. Other Bass are like picky or finicky eaters. They take the time to look the meal over. observe it from a couple of angles, follow it for a bit and then maybe bite and spit it out once or twice before deciding it is food.

FM