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The De-Evolution of the Ocean 290

An anonymous reader writes to mention an LA Times article entitled 'A Primeval Tide of Toxins.' The article looks at changing conditions in the world's oceans, and the resulting explosion in the growth of algae, jellyfish, and other primitive lifeforms. From the article: "In many places -- the atolls of the Pacific, the shrimp beds of the Eastern Seaboard, the fjords of Norway -- some of the most advanced forms of ocean life are struggling to survive while the most primitive are thriving and spreading. Fish, corals and marine mammals are dying while algae, bacteria and jellyfish are growing unchecked. Where this pattern is most pronounced, scientists evoke a scenario of evolution running in reverse, returning to the primeval seas of hundreds of millions of years ago. Jeremy B.C. Jackson, a marine ecologist and paleontologist at the Scripps Institution of Oceanography in La Jolla, says we are witnessing 'the rise of slime.'" The article is parting of a just-beginning series on our changing world called Altered Oceans.
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The De-Evolution of the Ocean

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  • by Tackhead ( 54550 ) on Friday August 04, 2006 @06:10PM (#15849232)
    They tell us that
    We got our tails.
    Evolving down
    To little snails.
    I say it's all
    Just wind in sails.
    Were we once men?
    We were DE-VO!
    • god made man
      but he used the monkey to do it
      apes in the plan
      we're all here to prove it
      i can walk like an ape
      talk like an ape
      i can do what a monkey can do
      god made man
      but a monkey supplied the glue

      Question: Are we not men?
  • Wow (Score:4, Funny)

    by baldass_newbie ( 136609 ) on Friday August 04, 2006 @06:11PM (#15849238) Homepage Journal
    This is just like the American political scene.
    Who'da thunk it?
  • "DE"-evolution? (Score:5, Insightful)

    by Sebastopol ( 189276 ) on Friday August 04, 2006 @06:14PM (#15849258) Homepage
    Why is this devolution? It is simply selection pressure: the higher life forms are pressured into extinction, and the jellyfish and algae go back to evolving: one taxonomy branch is pruned so that another may try. That IS evolution (well, a big hoerkin' chunk of it).

    • Re:"DE"-evolution? (Score:5, Interesting)

      by Mark of THE CITY ( 97325 ) on Friday August 04, 2006 @06:26PM (#15849328) Journal
      Disclaimer: I have a Ph.D. in chemistry but am not a marine environmental researcher.

      What is happening is a massive die-off of many highly adapted species, which, directly or indirectly, depended on oceanic dissolved oxygen being higher, pH being slightly alkaline, and toxin levels being lower.

      A big culprit here is phosphate and nitrate fertilizer runoff; read the series for all the details.

      Re-evolution may take as long as the first time; don't hold your breath!
      • Re:"DE"-evolution? (Score:5, Insightful)

        by lubricated ( 49106 ) <> on Friday August 04, 2006 @07:56PM (#15849712)
        well, I'm a biology grad.

        In general during extinctions it is the specialists that do poorly and the generalists that do well. The opposite is true other times.
      • If you have evidence of this, you really should take it before wolrd governments and encourage them to create a sanctuary or gene bank so that we can fix the problem once its effects on humanity are eventually realized.
      • Re:"DE"-evolution? (Score:3, Interesting)

        by kestasjk ( 933987 )
        Re-evolution is rather flattering, it implies that we're the end result of evolution; but it's silly to think that our more distant cousins are 'less evolved' than us because they're smaller/not-conscious. They have been around for just as long as we have, and if they have changed less than us that only shows how successful their genes are.

        I haven't seen the word 'evolution' consistantly misused like this since Pokemon.. "Gather 'round everyone, this Bulbusaur is EVOLVING!"
    • Re:"DE"-evolution? (Score:5, Insightful)

      by JDevers ( 83155 ) on Friday August 04, 2006 @06:28PM (#15849337)
      Exactly. Why does everyone think that evolution only leads to more and more complex life forms? Evolution is simply the never ending meat grinder getting the most out of the available resources. More often than not simple life forms are actually favored, which is why we live in a world with a thousand species of bacteria for every "higher" life form and a few billion individual bacteria for every "higher" life form.

      We (meaning animals) are almost an anomaly, not the rule. Anyway, as you said, as the environment changes so do the life forms that thrive in it. The very small are generally more able to cope with changing environments so they definitely win out in the short term.
      • Here's a question for you: Why does everyone assume that evolution is a good thing? Yes, species going extinct is just a part of evolution, but that doesn't mean we shouldn't care about it. Some of use would rather not have to wait ten million years before we can have fish for dinner again.
        • Here's a question for you: Why does everyone assume that evolution is a good thing?

          • We exist because of evolution.
          • The world around us exists because of evolution.
          • Evolution helps living beings endure their surroundings more effectively.

          Just to name a few. I'm sorry to say this, but you having fish is absolutely meaningless in the grand scheme of the survival of this planet's biology. As a matter of fact, the survival of our whole species is relatively unimportant.

          • And the survival of our planet's biology is relatively unimportant to the survival of our planet.
          • As a matter of fact, the survival of our whole species is relatively unimportant.

            Importance is a feature of cognition, not of things. We don't have access to a non-human category of "importance." Insofar as the term is meaningful at all, it is meaningful to humans. (When we have access to the epistemology of a dolphin, we can start to "translate" the idea of importance to its dolphin-equivalent.)

            So, if the survival of our species, the very precondition for anything being "important" as we understand it, isn
        • Re:"DE"-evolution? (Score:5, Insightful)

          by dan828 ( 753380 ) on Friday August 04, 2006 @08:42PM (#15849902)
          Evolution is neither good nor bad, it is a description of what happens. It's kind of like calling gravity or relativity good or bad. There also is no such thing as "de-evolution." Evolution is the change of allele frequencies within a population over time due to differential reproductive success. If this results in a "simpler" form of organism or the extinction of the species all together, it's still evolution. Of the five great extinctions to hit the earth, none of them caused any "de-evolution," they just killed off a good portion of extant species and left a lot a niches open for the survivors to exploit. We might be at the begining of the next great extinction event (though I doubt it'll get to that point, as I think we'll clean up our act before it happens).
          • Actually, we just don't think there was a widescale reversion to earlier life forms, but our evidence is on the million year scale not the fine grain needed to see this sort of thing. When a large number of organisms die out, they leave a lot of open niches and organisms rapidly fill in these recently opened niches. From a distant enough perspective it would just look like things as normal but a bit faster. I imagine if we were PRESENT and INVOLVED in one of the great die-offs, our perspective would be q
    • Re:"DE"-evolution? (Score:5, Insightful)

      by Michael Woodhams ( 112247 ) on Friday August 04, 2006 @09:32PM (#15850087) Journal
      That was pretty much my thought when I read the story.

      Bacteria are no less evolved than us. They've had the same 3-4 billion years, with more intense selection pressure* and much shorter generation times. They are exceedingly well optimised, and are the dominant branch of life on Earth.

      * The larger a population, the more effective evolution is. This is standard nearly-neutral population genetics, demonstrated by Kimura.

      Remember those museum displays labeled "Age of bacteria", "Age of Fish", "Age of Amphibians", "Age of Dinosaurs", "Age of Mammals"? They should have read "Age of Bacteria", "Age of Bacteria (plus a few multicellular marine organisms)", "Age of Bacteria (plus a few multicellular marine and land organisms)". Bacteria dominated the past, they dominate the present, and will be thriving when vertebrates are extinct.

      Consider (as is commonly done) the history of life on Earth as a day (but ending with the end of life on Earth, rather than ending with today.) The Earth will be sterilised by the red-giant phase of the sun, in about 5 billion years. Taking life as starting 3 billion years ago, the Age of Bacteria lasts 8 billion years, and on our 24 hour time scale, that means it is now about 9am.

      Cue music from "Hair":

      This is mid-morning of the Age of Bacteria
      The Age of Bactera
      Bacteria! Bacteria!
  • De-evolve? (Score:4, Informative)

    by amstrad ( 60839 ) on Friday August 04, 2006 @06:16PM (#15849265)
    Evolution is not directional, so the ocean cannot de-evolve.
  • by PIPBoy3000 ( 619296 ) on Friday August 04, 2006 @06:16PM (#15849267)
    It's funny when people claim that things are evolving into "higher" or "lower" forms, as if people are the obvious pinnacle of the process.

    What's happening is that the rate of change in the environment is faster than many species can keep up. When you have 10,000 individuals in a population and they breed every 5 years, they can only "absorb" so much change. When you have a species that has billions of individuals and reproduce every 20 minutes, they can take massive environmental change and thrive in it.

    The genetic diversity in the bigger population is vast and there's bound to be some individuals with higher tolerance of whatever the change is, be it increased temperatures, environmental toxins, or loss of food supplies. If one individual has the gene that boosts survival, it can propagate through the species very rapidly due to short lifespans.

    Think of the human species as the biological equivalent as a comet hitting the earth and you've got it about right.
  • "De"-evolution? (Score:5, Interesting)

    by imemyself ( 757318 ) on Friday August 04, 2006 @06:19PM (#15849276)
    I'm not a biologist, but why is this de-evolution? Evolution is just organism's adapting to their environment over many generations through natural selection. There have been plenty of times when simpler organism's triumphed when more complex ones failed. Take the dinosaurs for instance. Simple things like cockroaches and small rodents survived while the much larger and more complicated dinosaurs died out. Types of bacteria have been around basically forever (as far as life on the Earth is concerned).

    Really, (again, I'm not a biologist) it seems like simpler organisms are generally the things that make it through massive changes in the enviornment, because the more complicated animals are too-adapted to the current condiditions and can't evolve fast enough (too long of lifespans maybe?). The exception to this might be animals (humans) that are smart enough to either adapt their enviornment to them (for better or worse), or use tools to protect themselves from that change.
    • Re:"De"-evolution? (Score:5, Interesting)

      by the phantom ( 107624 ) * on Friday August 04, 2006 @06:39PM (#15849387) Homepage
      Minor nitpick: Organisms do not evolve, populations do. Otherwise, your post is right on. The more highly adapted species (specialists) are capable of filling only very specific niches. When that niche disappears, the population either changes, or dies out. If the change to the environment/niche is very rapid, the species is unlikely to be able to adapt quickely enough, especially if they have longer life cycles and small populations (relative to, say, bacteria). Less highly adapted species (generalists) have a better chance at survival, especially if they have shorter life-spans, and larger populations (which imply greater genetic variability), as it is likely that the genes needed to survive in the new environment are already present in some sub-section of the population, and only need the chance to spread.
  • that the more complex an organism the more it is adapted to it's niche environment and the easier it would be to affect it's ability to reproduce when stresses are added to said environment.
    • by timeOday ( 582209 ) on Friday August 04, 2006 @06:32PM (#15849354)
      Of course it is reasonable. Of course it is cause and effect. The question is whether we want to keep causing these effects. I for one would rather not leave the world to mold and cockroaches, even if they are superior in the darwinist sense of adapting to environmental devastation. Let's think deeply about this for a moment... 1) pollution is bad for complex, "highly-evolved" organisms; 2) people are such organisms; 3) you and I are people; 4) do you get it yet?
  • by quokkapox ( 847798 ) <> on Friday August 04, 2006 @06:21PM (#15849300)

    We humans are drastically changing the environment. In this century we will see mass extinction. We will also see mass adaptations and new speciation. The hardiest and most successful new species may turn out to be the bacteria and engineered organisms and ultimately nanotechnological devices that can break down and reprocess our industrial waste. Who is to say all of this isn't natural? We're 100% natural, we evolved here and we're part of this system. Whatever we do, it's natural by definition.

    The question is, what do we place value upon keeping around? The polar bears, the coral reefs, the rain forests? Polar bears are cute. Have you ever walked through a forest? I'd like for my kids to be able to go diving someday...

    • by kfg ( 145172 ) * on Friday August 04, 2006 @06:31PM (#15849348)
      Polar bears are cute.

      Try lookin' at one from the inside.

    • You're falling into a semantic pot hole:

      Man is natural. Therefore, anything manmade is natural, not artificial.

      Here, try this as an antidote:

      By definition, anything manmade is artificial. Anything not man made is natural. Man did not create himself, therefore man is natural.
  • Let's eat algae! (Score:4, Interesting)

    by erroneus ( 253617 ) on Friday August 04, 2006 @06:25PM (#15849321) Homepage
    Whatever the cause, over-hunting, over fishing, toxic waste, global warming, it means something to us in terms of food. People talk about environmental changes in terms that don't mean quite so much as food. If it affects our food supplies, then it really affects us.

    As far as "de-evolution" is concerned, it'll take another 500 million+ years before anything "new" comes about if ever. But what it does mean is that we will likely starve to death before we see whatever comes next.
  • hmmm (Score:5, Interesting)

    by the_other_one ( 178565 ) * on Friday August 04, 2006 @06:31PM (#15849347) Homepage
    Does anyone have any good recipies for jellyfish and algae?
    • I know you ask in jest, but here's a real answer.

      Don't know about algae, but jellyfish is a common appetizer in Chinese restaurants. You can also buy "mix it yourself" packs in just about any Chinese grocery store.

      Very delicious stuff. Damn, now I have a craving for it...
    • Re:hmmm (Score:3, Interesting)

      by shawb ( 16347 )
      My guess would be that there are some good recipies for this in Japan. I know that there are various algae that are extremely popular (Nori, the green stuff that sushi is often rolled in (among other uses) is a type of seaweed, of which pretty much all are algae.) Spirulina is what people would more identify as algae, and is often used as a food additive. Soylent blue-green anybody? I think algae would just about win the crown for efficient nutrient production out of any foodstuff... can be grown in fre
    • Jello brand gelatin.
    • Nothin's better than a soylent green biscuit with jellyfish spread... Mmm...
    • We can come up with all kinds of fun scientific observations as to the decline of larger, tastier species.

      Or, perhaps, we could see if there's an answer in the question posed:

      Why is it that tasty species are less able to survive in an environment where humans massively overfish and refuse to stop citing economic hardships?
  • Just Life's Cycle. (Score:5, Interesting)

    by Vegeta99 ( 219501 ) < minus city> on Friday August 04, 2006 @06:32PM (#15849355)
    I'm from Williamsport, PA. At one time, that small, now drug-ridden city was called the "Lumber Capital of the World", and had the highest level of millionaires per-capita in the entire world. Unfortunately, demand for lumber rose a little faster than the trees did, and now is not the same. In 6th or 7th grade, we went out to a nature preserve (that the power plant owns - I believe the government made them due it due to all the coal pollution). He explained to us why there were so many evergeen trees in the area and not much in the way of deciduous forest. The explanation seemed pretty logical to me - Once everything in the forest was killed off by the lumberjacks, it pretty well fucked up the ecosystem. But life isn't so easily put off. First, the lesser photosynthetic life returns, ferns, small plants, etc. and so on up until you finally get pine trees, and then deciduous trees. Animal life takes just as long to return. I never saw an elk until I was probably 16 or so (I'm 20 now.), and now they actually auction off a few elk tags a year.

    Once we figure out how to stop destroying our oceans, the balance will correct itself, but it will take many, many years. I kinda wonder how long until my hometown returns to it's former affluent ways (ha.).
    • "the government made them do it due to all the coal pollution"

      I don't mean to be a grammar Nazi, but I point this one out because for those of us who don't pronounce "do" and "due" the same (I say them as "doo" and "jew" respectively), it can be really hard to understand.
  • Caulerpa taxifolia (Score:5, Informative)

    by orbitalia ( 470425 ) on Friday August 04, 2006 @06:36PM (#15849376) Homepage
    Caulerpa taxifolia seems to be a good candidate for taking over the worlds seas and oceans.

    Originally a genetically modified strain was found that survived well in aquariums in Germany, and this strain was accidently released by the Oceanographic Museum of Monaco, it quickly spread and seems to be impossible to destroy effectively. As it is asexual technically it is the same plant, there is no known predator apart from one slug I think. It is currently spreading like wildfire and nobody really knows what to do. It easily spreads via ships ballast tanks, and the plant is toxic. [] ad/ew_caulerpa.en.pdf []

    A real disaster in the making..
    • Originally a genetically modified strain was found that survived well in aquariums in Germany,

      Oh for fuck sake, it was *not* "genetically modified". It was simply a naturally occuring strain that was *found* in the ocean by people looking for a strain of seaweed that would survive well in aquariums. If anything, this is a classic example of evolution in action! But, hey, it's so much more fun to pull out the "genetically modified" boogeyman, isn't it?
    • The strain in question wasn't genetically modified, at least not deliberately. According to the links you gave, it was exposed to tank chemicals and lighting, and that exposure appears to have caused it to mutate and gain increase ability to survive in cold water -- it's naturally found only in the tropics.

      Also, it's not 'impossible to destroy effectively'. The PDF you linked to describes several methods that have been found effective, but only for relatively small infestations, like those that have been found in the United States and Australia. Introduction of the animals that eat taxifolia in its natural locations would probably clean up big infestations, but the effects of further alien introductions are nearly impossible to predict. So far it's spreading like wildfire only around the Mediterranean, but other temperate waters have to be watched for infestations (warmer waters aren't at risk, because they already have taxifola and its predators, and colder waters aren't at risk, because even this strain of taxifolia can't stand that much cold).

      So, it's a cause for concern around the temperate waters of the world, but only a potential disaster in the Mediterranean area. It's similar to the Zebra Mussel, which is causing significant harm to the freshwater lakes and rivers of North America and Sweden.

    • One day, you may look at the menu at Red Lobster and find 26 different slug dishes.

      PS: Shame on you for being deliberately misleading about the "GM" stuff.
  • "The article is parting of a just-beginning series on our changing world called Altered Oceans."

    Leaving so soon? Could you please show the icebergs the way out, while you're at it?
  • Now I'm just waiting for everyone to start collapsing into this primordial sea...
  • It's a beautiful world we live in
    A sweet romantic place
    Beautiful people everywhere
    The way they show they care
    Makes me want to say
    It's a beautiful world
    For you
    It's a wonderful time to be here
    It's nice to be alive
    Wonderful people everywhere
    The way they comb their hair
    Makes me want to say
    It's a wonderful place
    For you
    Tell me what I say
    Boy 'n' girl with the new clothes on
    You can shake it to me all night long
    Hey hey
    It's not for me

    On a rather more serious note, it's already happening. In the Baltic sea, for exa
  • There is hope (Score:4, Informative)

    by Anonymous Coward on Friday August 04, 2006 @06:49PM (#15849427)
    Lake Erie was pretty much dead in the 1970s. Agricultural runoff and phosphate based cleaning products in sewage had acted as fertilizer for the algae. The algae took all the oxygen out of the water and the fish had died off. We changed a couple of laws and banned a couple of chemicals and fish returned to Lake Erie. If we had the will, we could do the same for the oceans. We have managed to ban ozone depleating chemicals for instance. Of course, we still have to solve the problem of various European nations (Spain comes to mind) completely stripping all the fish from wherever their fleet goes.

    The solution is just a matter of international political will.
  • In my opinion, this is analogous to the switch from Dumb Terminals to Desktop Workstations and then back to Thin Clients in corporate America ... it's just a cycle. Eventually it'll swing back in favour of the big fish. :)
    • Well, sure . . . (Score:4, Insightful)

      by StefanJ ( 88986 ) on Friday August 04, 2006 @07:27PM (#15849599) Homepage Journal
      . . . but if you rewind the VCR of evolution and let it play again, the show won't be the same.

      It could tens of thousands of years for all the niches to re-fill. And because ecological niches are defined in large part by what life is already around, the new species that arise won't be the same as the ones we are used too and benefit from.

      We could end up with an ocean without fish worth eating. They could be bony or greasy or, like a lot of fish species, poisonous.

      And the human survivors living in the depleted, impoverished ecosystems we leave behind will utterly despise us for our careless, irresponsible, wasteful ways.
  • Something changed the environment and the DINO's left the scene..

    We changed the ocean, beyond the ability to adapt, of large animals with often long cycles between generations...

    Small life with rapid breeding cycles can adapt much faster, etc... so it's not surprising that they
    are thriving in a eco system increasingly devoid of some the larger predators..

    But I see it as more of the ebb and flow of evolution then it working "forward" and in "reverse." That's
    a rather false dichotomy. Evolution just works.. th
  • Dirty mind (Score:5, Funny)

    by DCstewieG ( 824956 ) on Friday August 04, 2006 @07:03PM (#15849484)
    I'm sorry, I just had to point this sentence out:

    With a tug on the trip-rope, the bulging sack unleashed its massive load.
  • 20th century
    "the way the beach is kissed by the sea,
    poluted now but in our hearts still clean"
    --Insane Jane in a tribute to Pete Townshend)

    21 century
    "Jellyfish heaven - were Jellyfish go
    to get away from mormons - and drunk eskimos
    jellyfish heaven
    is a lot
    like L.A.
    --Dead Milkmen

  • This won't happen (Score:3, Insightful)

    by Myria ( 562655 ) on Friday August 04, 2006 @07:07PM (#15849496)
    This is assuming that this damage to the oceans can continue indefinitely. A massive extinction of marine animals would make its way up the food chain. Land life would eventually be affected, both by the stuff we're already doing and by the extinction of their marine food. Eventually, it will affect humans. We'd start dying off too, leading to basically a collapse of civilization. It would return us to the stone age. With civilization gone, the damage to the oceans will stop.

    It's very hard to kill all humans. Even now we don't have enough nukes and chemical weapons to kill every single person on Earth. You can probably get 99%, but that still leaves 62,000,000...

  • Piffle (Score:5, Funny)

    by Quiet_Desperation ( 858215 ) on Friday August 04, 2006 @07:14PM (#15849535)

    The new, better toxic oceans will simply be a tought playing field for our watery bretheren. The competition will be fierce, but in the end the seas will be populated by new fish. Better fish. New, better races of ATOMIC SUPERFISH THAT I SHALL BEND TO MY WILL AND RULE THE WORLD! Ha ha ha ha! Despair, ye mortals, and weep! Oh, Discordia!

    Imagine! Goldfish that shoot lasers from their eyes! Tuna that can bite through adamantium! Shrimp that can do your taxes! Coelacanths that can write bug free code! Oh, the mind wobbles. More toxins! DUMP MORE TOXINS, DAMMIT!

  • Government officials thought they were helping in the early 1990s when they released fresh water that had been held back by dikes and pumps for years. They were responding to the recommendations of scientists who, at the time, blamed the decline of ocean habitats on hypersalinity -- excessively salty seawater.

    The fresh water, laced with farm runoff rich in nitrogen and other nutrients, turned Florida's gin-clear waters cloudy. Seaweed grew fat and bushy.

    It was a fatal blow for many struggling corals, delica

  • From the British Royal Society:

    "Ocean acidification due to increasing atmospheric carbon dioxide" []

    One possible consequence, down the road: Ocean waters become acid enough to prevent phytoplankton from forming exoskeletons.

    Which means the entire marine ecosystem collapses, and Red Lobster is reduced to offering All You Can Eat Guppy Fry-Days. (Oxygen fee waived for parties over ten.)
  • FTFA
    some of the most advanced forms of ocean life are struggling to survive while the most primitive are thriving and spreading. Fish, corals and marine mammals are dying while algae, bacteria and jellyfish are growing unchecked.
    So algae and jellyfish are primitive, and corals, which are essentially jellyfish infected with algae, are advanced. Got that?
  • Words, words... (Score:2, Informative)

    by alexgieg ( 948359 )
    The text is misleading in the way it defines the word "evolution". It equates "more evolved" with "complex", and "less evolved" with "simple". This isn't correct. "Evolution", at least in biology, which is the topic here, is a concept almost synonym to "adaptation". Any life form able to survive in a given habitat is as much "evolved" as any other life form that is also able to survive in that habitat. The amount of cells it's composed of has no meaning to this. If algae are able to survive in the new ocean
    • Easily the most intelligent and relevant post in this discussion. How did TFA's author get the daft idea that complex organisms are more "advanced" and simpler organisms more "primitive"? Isn't the premise of the article -- that it's the simpler organisms that are more successful -- enough to put paid to that kind of nonsense?
  • some of the most advanced forms of ocean life are struggling to survive while the most primitive are thriving and spreading. Fish, corals and marine mammals are dying while algae, bacteria and jellyfish are growing unchecked.

    This would seem to make perfect sense really. We are causing change, and evolution is made to cope with it. Smaller, simpler lifeforms are able to cope with change a lot easier than large complex organisms. The main reason for this is the life cycle for a plankton is what, 4 weeks?
  • by porcupine8 ( 816071 ) on Friday August 04, 2006 @10:09PM (#15850229) Journal
    Evolution can't "run in reverse." Evolution doesn't have a goal or a direction. Natural selection says that whatever organism is best adapted to a particular environment/nice will reproduce more. It doesn't say that that organism must be more "advanced" or complex than the ones that were in the niche before. Less complex organisms are better able to adapt to the changes happening in these particular environments. Maybe they'll get some new adaptations eventually that lead to their becoming more complex. Maybe not. Maybe the environment will change again to favor the more complex creatures. Maybe not. But it's certainly not running "in reverse."

Always leave room to add an explanation if it doesn't work out.