Why Sex With Creatures from the Future Is a Bad Idea

I wonder if it's more a length of dormancy that is effecting things rather than just the generational advancements. The article seems to completely ignore the cost of dormancy on genetic information.

Playing Devil's Advocate since 1978

"The only constant in the universe is change"
-Heraclitus of Ephesus 535 BC - 475 BC

Yeah I'm a bit curious as to why they had shorter lives?

Were the mating habits different between the generations? (i.e. amplexus) Were there actual pathogens... or shrimp STI's STD's that the older generation was unable to deal with?

I guess maybe those are questions for another study.

Also... I'd like to point out that it's the journalist who is extending the results of the shrimp study to humans and drawing untested conclusions about humans based on it... before all the science hating zealots start posting nonsense comments attacking the merits of this study.

@CodeZero,

I think the claim is that anabiosis doesn't degrade any genetic information (at least not during the timeframe of the study)

@CodeZero, I am inclined to agree. I suspect it's not a difference in generations so much as it's a result of the older eggs being stressed over the longer time span of dormancy before hatching. I wonder if they actually did any comparative analysis between members of the same generation and of their immediate parent/child generations once-removed? As usual, not enough information given in these brief articles to give us a bigger picture of scope and scale on these experiments and trials.

time travel? no. this is more alone the lines of breeding a woman with the frozen sperm of a caveman. cross breeding multiple generations of brine shrimp doesnt equate to time traveling sex.

The study does lay parallel with the proposed lines of human colonization theories, suspend human genetic structures to be reanimated far away... the term "time travel" is being thrown around loosely. And without proper information, I have to lean heavily on the degregation of the suspended genetic structures than on an odd rejection due to the time span / generational gaps. If it were antagonistic coevolution, as the article states, would'nt the very act of fertilization be compromised, rather than successful fertilization resulting in nothing more than a shorter lifespan. The lack of mutation, infertility, or any other obvious genetic defects is confonding me slightly. To simply have a shorter life span... Maybe we are missing a piece of the puzzle that we don't even know exists. There are theories of Genetic knowledge and other forms of inherited information passing that we do not fully grasp yet. Saying flatly that if you travel in time and try to impregnate a woman from either the past or future that the resulting child will have a shortend life span is far too much of a stretch to even bring into context. But as stated above, it was the author not the scientists that made this bridge.

Playing Devil's Advocate since 1978

"The only constant in the universe is change"
-Heraclitus of Ephesus 535 BC - 475 BC

"I suspect it's not a difference in generations so much as it's a result of the older eggs being stressed over the longer time span of dormancy before hatching."

The article says the control group was females that mated with their own generation. These lived longer than those that mated with "future" males, eliminating the confound that the older eggs had lived in dormancy for decades.

This is a worthwhile study, it brings up so many questions. First rule out concerns about anabiosis and amplexus by proving that males *and* females that have undergone 22 or however many years of dormancy will live as long as current generations by mating them with other shrimp from the same dormant population. Do we know whether lab-grown brine shrimp 160 generations ago simply lived shorter lives? Are we talking about 160 continuous generations of the same lab-grown gene pool? Were the 1985 and 1996 generations wild-caught or lab grown, and if so, for how many generations? What was the duration of amplexus for males in 1985? Etc...

Differences in the lab 'ecology' 22 years ago may also be a contributing factor - including anything from ambient BPA concentration to lighting to wifi. Who knows?

The title is catchy, but it may actually be different for other species that start out more vigorous and become less so with time. On the other hand, even though so many science-fiction stories riff on the theme that future generations might come back in time to mate with their 'less-evolved' ancestors, what's the possibility that genes from previous generations might be worse genetically-speaking than mating with siblings for the same reasons?

why would a time traveler be worried about sex? i'm pretty sure they have way more important things to worry about.

"The longer the time-shift, the earlier they died: The 22-year time difference shortened female lifetimes by 12 percent; the effect was 3 percent for the 11-year time-shift."

Jennifer, couldn't this be restated, though, as the longer the egg'd been preserved, the more likely the female was to have a shortened life?

If we were talking about tins of corned beef no one'd bat an eyelid if told the cans opened after 22 years were more likely to be tasteless and of reduced quality than the cans opened after 11 years.

My point being, this study'd be more convincing if they'd run a control group experiment showing revived females' life expectancies weren't affected deleteriously after mating with revived male contemporaries.

Saying all that, I approve of taking conventional experiments and exploring them from a novel perspective, because even if they fail, they show the conventional perspective is just that - a convention which, if forgotten, can sublime unnoticed into unquestioned assumption then dogma.

I also think your headline and presentation shows creative energy and effort on your part to freshen up what could easily become a stolid if not boring report, rather than as some seem to think, mere carny huckstering to draw in mug punters.

@JediMindset: "why would a time traveler be worried about sex? i'm pretty sure they have way more important things to worry about."

They might be concerned about accidentally making Luke Skywalker Darth Vader's dad, and therefore Princess Leia her own granddaughter and grandmother!

Many of you pose some great questions about the study. I'll answer a few here. Most important, *all* of the brine shrimp--females included--were hatched from preserved eggs, and all three generations of both females and males were mated with each other. For example, females from 2007 were mated with males from 1985 (and vice versa). As one of you suggested, this resolves length of dormancy as a confounding factor because the deadly effect of intergenerational mating was seen in all the females, regardless of how old the female (or male) eggs were. "You would not expect this pattern if the cost of dormancy was only involved," Nicolas Rode wrote in an email last night. A few other answers: The eggs were all from a wild population from Utah's Great Salt Lake. And, to quote the study, "tray position on the lab shelf was weekly randomised in order to avoid local shelf effects."

@alanborky
or that one scenario in the Terminator movies. where his father goes back in time to impregnate his mother.

1. The females that mated with a male that was from 160 generations back in their past were horrified when they realized that the guys that they had been dating were just as crude and primitive as the relative caveman they had just encountered, and the notion that their entire species had obviously hit a complete dead-end evolution-wise sapped their will to go on.

2. The females that mated with a male that was 160 generations younger then them found their public reputations ruined by accusations of cradle-robbing and, in some nasty cases, pedophilia, and science has long known that societal outcasts have a tough row to hoe.

Do cryopreserved human eggs and sperm produce people with shorter lifespans, I wonder. Guess it's too soon to test that out.

I'm gonna trust future condoms working better than the ones today.