Evolution as it happened, plus wet walkers

Pink handfish. No source information available.

Pink handfish. No source information available.

First up, there’s a great (if busy) illustration of the evolutionary ‘tree’ here. As you can see, it’s not so much a tree as a densely packed root system, with most extinctions removed (because otherwise it just look like a solid mass).

And in recent news, scientists have discovered a new species of walking shark. There’s a fascinating video in that article, showing the shark walking along the sea bottom, using their pectoral and pelvic fins to push them along.

Axolotl. Image by Stan Shebbs, licensed under GNU FDL.

Axolotl. Image by Stan Shebbs, licensed under GNU FDL.

There are also a number of walking fish. The axolotl, or Mexican walking fish, is probably the best known, but the waters around south-east Australia are home to 14 species of handfish, who use their hand-like (and footlike) fins to walk along the bottom. If you look at the 4 photos in this National Geographic article, you can see from some of them that there are two fins placed like legs, which is quite unusual for a fish.

The handfish species are all considered threatened to some degree or another – they only live in shallow coastal waters off south-eastern Australia, and individuals tend to stay close to their homes. So their genetic diversity is probably quite low, putting them in danger, as they’ll be less able to weather any threats such as climate change. Scientists are hoping that the clean-up of the Derwent river may help the species to bounce back, by reducing the threat from pollution.

Although handfish are only found around Australia, fossils have been found in the Mediterranean, and scientists suspect the creatures may have lived in oceans around the world millions of years ago. If they’re currently restricted to a small area of shallow water near Tasmania, they’ll be unlikely to survive the warming waters that climate change will bring, as they’ll be unable to migrate to suitable shallows further south.

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5 Responses to Evolution as it happened, plus wet walkers

  1. gil says:

    i study biology and i think i have very strong evidence for design in nature

    a) we know that a self replicate robot that made from dna need a designer

    b) from a material prespective the ape is a self replicate robot

    a+b= the ape need a designer

    or even a self replicat watch.the evolution side always say that a watch need a designer because it cant self rplicat. so if we will find a self replicat watch we need to say that is made by itself

    plus: if a self replicate car cant evolve into an airplan, how can a bacteria can evolve into human ?

    the evolution say that small steps for milions years become a big steps. but according to this a lots of small steps in self replicat car (with dna) will evolve into a airplan.

    but there is no step wise from car to airplan

    evolution say that common similarity is evidence for common descent. but according to this 2 similar self replicat car are evolve from each other .

    • Alison Jobling says:

      Hi gil, and thanks for commenting. I’d like to reply to your comment piece by piece, if that’s okay.

      a) we know that a self replicate robot that made from dna need a designer
      b) from a material prespective the ape is a self replicate robot
      a+b= the ape need a designer

      No, you’ve defined the ape as a self-replicating robot.

      Your argument is similar to this:
      • Concrete is hard and humans designed concrete
      • Rocks are hard like concrete
      • Therefore humans designed rocks

      In other words, you’re saying that because we can (possibly, in your example) replicate something that occurs in nature, then everything that occurs in nature must have been made by someone.

      or even a self replicat watch.the evolution side always say that a watch need a designer because it cant self rplicat. so if we will find a self replicat watch we need to say that is made by itself

      No: evolution says nothing about watches, because watches don’t occur in nature, and evolution deals with things occurring in nature, not things that are manufactured.

      Also, you’re mixing up evolution and the origin of life. Evolution talks about how species change over time in response to evolutionary pressure from their environment – the best-suited to survive will survive and pass their characteristics to their offspring. When we talk about origin of life, we’re talking about the jump from non-self-replicating molecules to self-replicating molecules. They’re two entirely different topics.

      plus: if a self replicate car cant evolve into an airplan, how can a bacteria can evolve into human ?

      Very simple self-replicating molecules (not bacteria) did evolve into humans, and that happened through random mutation and natural selection over millions of years. Random mutations happen. Individuals that have a competitive edge over other members of their species have a better chance of survival, and so have a better chance of reproducing and passing those characteristics on to their offspring. That’s natural selection. Combine these two mechanisms over millions of years and you get the evolution of species.

      the evolution say that small steps for milions years become a big steps. but according to this a lots of small steps in self replicat car (with dna) will evolve into a airplan.

      No: there’s no current push to make that car evolve into an airplane – in biological terms, there’s no evolutionary pressure. A self-replicating car would continue to replicate as is, until/unless circumstances changed and it was no longer suited to its environment. At that stage, the changed circumstances might favour one particular mutation, to the extent that that mutation is better able to survive and reproduce, and that would be a first step towards your car evolving into an airplane.

      Or it might evolve into an amphibian vehicle, or a tunneling machine, or something else, depending on the environmental conditions that prompted the evolution. Or the car species might just become extinct, if it couldn’t adapt sufficiently fast.

      evolution say that common similarity is evidence for common descent. but according to this 2 similar self replicat car are evolve from each other.

      Not quite: evolution says that common similarity of species is evidence for common descent, not similar individuals. Your 2 similar cars would both be part of the same species, so one doesn’t evolve from the other.

      • gil says:

        hi again

        again.

        you said:

        “No, you’ve defined the ape as a self-replicating robot. “-

        from a marerial prespective why not actualy?

        ” you’re saying that because we can (possibly, in your example) replicate something that occurs in nature, then everything that occurs in nature must have been made by someone.”-

        not. i just say that a robot with dna need a designer.

        “No: evolution says nothing about watches, because watches don’t occur in nature”-

        acctually thay are a product of humans. so they are a product (side effect)of evolution.

        “Also, you’re mixing up evolution and the origin of life. “-

        you right. but we can talk abut a bacteria in a close room. if bacteria can evolve into human-then a car can evolve in a close room because the bacteria can evolve to a human and he will made a car.

        ” That’s natural selection. Combine these two mechanisms over millions of years and you get the evolution of species.”-

        but for new kind of animal we need a new systems. so the question is if there is a step wise to get a new system. can you as intellegent design. make a car in small functional steps?

        “No: there’s no current push to make that car evolve into an airplane – in biological terms, there’s no evolutionary pressure. “-

        why not? an airplan can fly and get is food better then a car.or run away from predators.

        “Or it might evolve into an amphibian vehicle, or a tunneling machine, or something else, depending on the environmental conditions that prompted the evolution. “-

        yep. but there is no stepwise to this systems also.

        “Not quite: evolution says that common similarity of species is evidence for common descent, not similar individuals. Your 2 similar cars would both be part of the same species, so one doesn’t evolve from the other”-

        not if they are in different models. like 2007 and 2008.

        have a nice day

      • Alison Jobling says:

        “No, you’ve defined the ape as a self-replicating robot. “-
        from a marerial prespective why not actualy?

        Because you’re using the logical fallacy of proof by example: you’re assuming that the ape (and by extension any living thing) is a self-replicating robot which needs a designer, and hence the ape needs a designer.

        “No: evolution says nothing about watches, because watches don’t occur in nature”-
        acctually thay are a product of humans. so they are a product (side effect)of evolution

        No, they are a product of human engineering – evolution has nothing to do with it.

        “Also, you’re mixing up evolution and the origin of life. “
        you right. but we can talk abut a bacteria in a close room. if bacteria can evolve into human-then a car can evolve in a close room because the bacteria can evolve to a human and he will made a car.

        Now you’re vastly oversimplifying the origin of life as well as evolution.

        ” That’s natural selection. Combine these two mechanisms over millions of years and you get the evolution of species.”-
        but for new kind of animal we need a new systems. so the question is if there is a step wise to get a new system. can you as intellegent design. make a car in small functional steps?

        New kinds of animals have evolved continually over the millennia – radically new kinds. But that evolution happened slowly, over a massive time scale. There was generally no stepwise evolution – gradual changes make subsequent generations more fit to survive and pass on their characteristics to their offspring.

        “No: there’s no current push to make that car evolve into an airplane – in biological terms, there’s no evolutionary pressure. “-
        why not? an airplan can fly and get is food better then a car.or run away from predators.

        Again, you’re misunderstanding the process of evolution: if there is no evolutionary pressure that favours new mutations over the current form, then there’s no reason for creatures to evolve. Just because you believe that planes are ‘better’ somehow than cars, doesn’t mean that there would be any pressures forcing the cars from their current niche. Cockroaches have been around in their current form for more than 60 million years, but since they are very well adapted to their current niche, and there have been no evolutionary pressures forcing them to evolve, they’re still around even though they’re not what most people would consider the peak of anything.

        “Not quite: evolution says that common similarity of species is evidence for common descent, not similar individuals. Your 2 similar cars would both be part of the same species, so one doesn’t evolve from the other”-
        not if they are in different models. like 2007 and 2008.

        You’re stretching your analogy well beyond breaking point here, I think.

  2. gil says:

    hi again alison.

    you said:

    “you’re assuming that the ape (and by extension any living thing) is a self-replicating robot which needs a designer, and hence the ape needs a designer.”-

    what is the diference actually? if i will made a robot with dna. is this kind of robot is not a robot?

    “No, they are a product of human engineering – evolution has nothing to do with it.”-

    if human engineering is a product of evolution- then it mey be true also.

    “New kinds of animals have evolved continually over the millennia – radically new kinds. But that evolution happened slowly, over a massive time scale.”-

    so how do we know that a one kind of animal can evolve into another?

    “Again, you’re misunderstanding the process of evolution: if there is no evolutionary pressure that favours new mutations over the current form, then there’s no reason for creatures to evolve. Just because you believe that planes are ‘better’ somehow than cars, doesn’t mean that there would be any pressures forcing the cars from their current niche.”-

    its just an example. you can choose any 2 complex object that you whant. can you, as intellegent designer change an mp3 into cell phone or anything by a step wise?

    have a nice day

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