New Zealand Tree Stuck In Evolutionary Time Warp 337
sciencehabit writes "A eucalyptus-like tree from New Zealand is still waging a battle that should have ended over 500 years ago. The tree continues to sport evolutionary adaptations, such as barbed leaves, to protect it from a large, flightless bird known as a moa. There's just one problem: the moa went extinct around 1500 AD."
evolution (Score:5, Insightful)
So, they're implying that evolutionary traits should disappear after a relatively short period? Why? I'd suspect they may fade away over centuries, but not necessarily.
In other news... (Score:5, Insightful)
The kangaroo still hasn't come up with a better way to bring up it's kids. Having your embryo climb all the way up to your pouch is sooo last Megennium.
Wrong comparison ? (Score:5, Insightful)
This does not prove anything.
Plant A, under evolutionary pressure, develops a mechanism with which it protects itself from moas.
Plant B, which is not under evolutionary pressure, does not develop such a system.
Evolutionary pressure disappears, but growing the defense mechanism does not constitute an evolutionary disadvantage, so it stays in place.
Under the influence of random mutations, some plants might revert back to the old style, but this is a big might, since evolution works more by accretion than by shedding things.
I really do not see anything relevant here.
Evolution is great. (mostly) (Score:3, Insightful)
Then one day by random chance a little tree will sprout that has smaller barbs, and if it survives might start a trend towards less pokey trees.
Something tells me none of us will be around by then unfortunately. I'd also wager the barbs help keep things like people and imported herbivores at bay as well, and until we go extinct maybe the trees will continue to poke when pecked, even if the poke is intended for extinct peckers.
Humans stuck in evolutionary time warp (Score:3, Insightful)
In other news, humans still have an appendix.
Just because something is useless doesn't mean evolution will remove it - its only when it becomes actually detrimental and individuals start removing themselves from the reproduction chain that things change.
Re:evolution (Score:5, Insightful)
Agreed. I originally thought the post was about trees that were CONTINUING to evolve. But simply having old adaptations is pretty uninteresting.... nay, normal. Especially for trees, which repopulate very slowly compared to say, fruitflies.
Anyway, the only reason for a species to "unevolve" changes that are no longer necessary is if they are very expensive, and no other side-effects make them beneficial. Barbed leaves may collect more rain and retain heat better than unbarbed leaves, and plenty of tree species have similarly pointed leaves, even when they're grown and well fed in managed woods and public parks.
Re:Wrong comparison ? (Score:3, Insightful)
growing the defense mechanism does not constitute an evolutionary disadvantage, so it stays in place.
Actually, the defense mechanism inevitably costs some energy to produce, and imposes design compromises that may affect the other functions of the plant. A mutant without these defenses will certainly have a fitness advantage.
However, while 1500 years sounds like a long time to us, it probably doesn't represent very many generations of these trees.
Just an idea... (Score:2, Insightful)
Presumptuous? (Score:2, Insightful)
It is a common misconception about evolution (Score:4, Insightful)
Intelligent design is simple, everything can be explained because a god decided it had to be so. So our eyes work the way they work because god said so and you can't go questioning god. However god is not perfect. Why are some men color-blind while some women can perceive an extra color? Why can't we see ultra-violet? Why is that other animals have 4 or even 5 cones while we got only 3? It doesn't sit well with the ID idea that birds and fish got far better vision then we do.
But evolution is NOT a perfect replacement. We humans are detectors of patterns. That is why we see a face on mars or jezus on toast. Simple test. Imagine me holding something between my fingers. You see a short squared long white piece of wood of perhaps 4mm x 4mm x 3cm. What am I holding? Be honest, you think it is a match isn't it? It is a fair guess. You KNOW that most pieces of wood shaped like this are matches because that is really one of the only reasons to shape wood like this. And you might be right EXCEPT I might ALSO be holding a would be match that hasn't yet had its head put on OR a "toothpick" used by dentist to wedge teeth apart.
As pattern seekers we like to think that everything has a reason and evolution does not. Evolution just is. In this case, there were a dozen sapplings some of which had leaves that the bird didn't see and which were eaten. The ones that weren't, survived to reproduce. With the bird gone, the selector is gone but not the reason for the change. Over time more and more of the leaves might change and since now there is no bird to eat them, they might survive. It could well be that the leaves we see now are FAR less good at camoflage then the leaves 500 years ago, but with no selecting taking place anymore, all the plants are surviving.
that is evolution. Random minor variations that result in different species if the enviroment forces a selection of what variation survives till reproduction.
But there is no goal to it. The plant did not choose to have a certain colored leave. Just random mutation. Some work, some don't. But unless someone causes you to be eaten for a mutation, then there is nothing wrong with it and if you can attract a female with it, then you reproduce.
the original article btw never implies that the plant should have changed back. Just the "editors" that picked the story up.
these articles and responses make me cringe (Score:2, Insightful)
Re:It is a common misconception about evolution (Score:5, Insightful)
No, the problem with intelligent design is, that although unworthy of discussion here, the editors very often edit evolution summaries to troll the /. readership.
Re:Evolution is great. (mostly) (Score:3, Insightful)
Bingo! You've stated one of the most basic points, yet most frequently overlooked. When you're talking about evolution, years is an almost totally meaningless unit. Generations is what counts, and for most logical analysis, it's the only thing that counts.
I've seen people here on slashdot babble about how viruses must have a higher individual mutation rate than advanced organisms, because they evolve so fast, and totally ignore that the virus may have a 1.7 day average reproductive cycle, and the advanced organism take an average of 20 years for one generation. How often an individual organism is a mutant may have little or no correlation to how long a species lasts before becoming a new species.
Now counting anything else besides survival as a success is more debatable... What if a species becomes a very specialized niche organism in the process of driving its predator to extinction, for just one example? In the article's case for another example, the plant defenses didn't actually contribute much if anything towards making Moas extinct, human presence did most of the work there, if not all. Big Drumsticks!
Terrible summary (Score:5, Insightful)
Five hundred years is completely negligible on an evolutionary timescale. If trees - TREES - you know, big woody things that grow really slowly - had evolved significant changes in that time it would be headline news.
The research that led to this story wasn't remotely aimed at calling evolution into question, quite the contrary. Scientists are interested in the causes of the changes that these trees go during their lifetimes - and they have shown that these metamorphoses are probably due to the moa bird. Which is quite interesting, if probably not Slashdot-worthy.
Re:It is a common misconception about evolution (Score:4, Insightful)
Re:evolution (Score:4, Insightful)
First it's important to notice that the number of generations for a tree over 500 years are fewer than for a human. So even a fifth generation can show very few differences. The trait may also stop other species from preying on the tree, even if it isn't obvious unless the trait disappears.
And if the cost of maintaining the treat is low it may not disappear for a long time.
Give it a few thousand years more and we'll see what happens. It is possible that it evolves into two forms, one with leaves that don't have barbs and one with barbs.
Clever Modding (Score:2, Insightful)
Re:It isn't instant. (Score:4, Insightful)
And humans still have tailbones.
It's a good thing, too, what with all the muscles and tendons that attach to the tailbone. What would they attach to if we didn't have a tailbone? I mean, can you imagine not having a tailbone as a vital part of the weight-bearing structure? We wouldn't be able to sit down.
Re:It is a common misconception about evolution (Score:5, Insightful)
No! We shall not succumb to your advocacy of taking our freedoms! We shal found Free Theology Foundation - FTF. We shall develop our religion, to oppose your monoteism: GNOM - GNOM's NOt Monotheism!
Re:Easily explainable. (Score:3, Insightful)
Its not about outgrowing greed - not possible we are talking about an deeply ingrained evolutionary tuned instinct.
It is about using just enough intelligence to not allow primitive instincts rule supreme in our societies. Just had a nice little demonstration in the financial industry, in case you didn't notice.
Re:It isn't instant. (Score:1, Insightful)
Remember Pascal's Wager and you'll have nothing to lose and everything to gain.
Oh but kafir, Pascal assumed that you only had one God to choose from. And you have chosen the wrong one, by ignoring the word of the Prophet Muhammad (peace be upon him). Alhamdulillah. Allahu Akbar!
Re:It isn't instant. (Score:3, Insightful)
Of those you listed, body hair is really the only one that could be treated genetically... obesity is largely a result of your lifestyle in most cases. Yes, there's some who don't have a choice, but most who are obese are that way because they eat too much of the wrong kind of food, and don't get enough exercise.
Similarly, while there's a genetic predisposition towards depression, a lot of people who suffer from it don't have that marker. Depression is largely due to circumstances and lack of a support network... a person is suffering from a life crisis and hasn't been equipped with the tools they need to deal with the emotions surrounding it.
Personally, I'm leery about when they start tinkering with our DNA to remove unwanted traits. What happens when they decide to apply it to something other than genetic diseases, and start applying it to things like a genetic predisposition towards homosexuality, or curly hair, or being short? When we lose our genetic diversity, we become significantly more vulnerable to outside influences, and the human race is already very shy on genetic diversity... the average colony of bonobos has more genetic diversity in 200 individuals than the human race has in 6 billion.
Re:evolution (Score:5, Insightful)
Here is what the article is about: "to understand the evolution of plant traits, you also need to look at extinct herbivores and their interactions with the plants." In other words, to see why something is the way it is, you may have to uncover evidence that is hard to find because things have changed. Is this a revolutionary idea? No. But they have discovered a likely reason why a particular plant has a curious behavior of changing dramatically mid-life. The article is simply telling that story, not scratching its head in why the plant hasn't lost this adaptation in the 500 years since the extinction of its former predator.
Re:Easily explainable. (Score:3, Insightful)
Oh, my. Greed, like entropy, doesn't have to be "ingrained". It's a direct and predictable result of the benefits, to individuals in a complex environment, of being greedy, much as entropy is a predictable result of complex systems allowed to have random interactions. And it doesn't take _intelligence_ to limit. Wolves, bees, even bacteria have ways to limit excess growth. These ways may be nasty: killing and eating those who hoard and wind up with most of the food, for example, is a nasty business.
Now, can intelligence often do a better job of limiting the destructive and maximizing resources for the species? Sure. That's why we have civilizations and cultures, to preserve and spread information to the next generation. But don't ignore those "primitive" impulses. It's like ignoring physics when you try to design a computer: it keeps popping up, and you can't just ignore it.
Re:Clever Modding (Score:5, Insightful)
Re:Clever Modding (Score:5, Insightful)
The additional growth required to change the leaves like that is going to be non-zero cost. Appendixes are more or less free (they're tiny). I also suspect that these trees would grow faster if they had big bright green leaves as saplings. So I figure there's one of two reasons they haven't evolved away: 1) it helps against deer too, there was only about 300 years without deer or moa, 2) they haven't gotten a random gene mutation to drop it in the last 500 years (500 years is pretty damn short)
Re:Easily explainable. (Score:3, Insightful)
Greed, like entropy, doesn't have to be "ingrained". It's a direct and predictable result of the benefits, to individuals in a complex environment, of being greedy, much as entropy is a predictable result of complex systems allowed to have random interactions.
No it does not have to be ingrained, and in fact will not be when the fixed-action patterns of behavior are "new" as far as evolution is concerned. However given enough time (again, as far as evolution is concerned), fixed-action patterns of behavior do and will become an ingrained instinct (as so much research has shown it is now accepted evolutionary theory [google.com]). This is so true in fact, that even knowledge passed on by parents to offspring, if significantly beneficial over time - becomes ingrained instinct that no longer needs to be taught. Again this is fixed action behavior, a category that Greed falls into. Humans are not going to instinctively learn how to drive cars - but they may instincvly learn to fear road crossings if enough people died, over enough time. Thats just how it works. Oodles of evidence supporting this, but to stay on the New Zealand them you can brush up a bit here. [natlib.govt.nz]
Now, can intelligence often do a better job of limiting the destructive and maximizing resources for the species? Sure. That's why we have civilizations and cultures, to preserve and spread information to the next generation. But don't ignore those "primitive" impulses. It's like ignoring physics when you try to design a computer: it keeps popping up, and you can't just ignore it.
Well, yeah. I suspect you don't get the point (I never said individuals can outgrow greed, never said it should be ignored - do your read the posts you reply to?). At a "civilizations and cultures" level greed is not only being ignored, but in most societies has been embraced as the modus operandi. Again, queue Financial "crisis" as a recent demonstration for your consideration - a small and completely insignificant event on the evolutionary scale.
Re:unity is perfect (Score:3, Insightful)
Re:In other related news... (Score:1, Insightful)
Actually, it's relatively easy to force the development of male lactation, and there are some societies in which it's standard for the father to do some nursing as well.