Does evolution always yield similar results?

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I've been watching these videos on YouTube recently about computer-generated robots that are given an algorithm in which they "evolve" to most efficiently move in a given environment. The researchers who observed this were amazed to find that almost all of the results resembled actual animals (i.e. legs and tails). When simulated in an underwater environment, the robots evolved into fish-like shapes and swam in a similar way. To prove the legitimacy of the algorithm, the researchers created their own robots in the shapes of actual animals (a pig and a koi fish) and let the algorithm work out how they would move, and the algorithm came up with a surprisingly similar pattern to that of the real animals.

So this brings me to a question: does evolution always yield similar results? As another relevant topic, the red shell that many sea animals like crabs and lobsters have is so efficient that multiple species have evolved it entirely independently. Even in societal evolution, similar patterns can be observed. Isolated cultures with no contact with each other tend to develop the same technologies around the same time. Two separate people invented the telephone in the exact same decade. This leads me to another question concerning life on other planets: would intelligent aliens be fairly similar to humans, and other life on their planets be similar to life on Earth? Obviously, depending on the climate and geographic variables of the planet, they'd still be considerably different, but would basic structures - bipedal legs, opposable thumbs - which contribute so heavily to our technological superiority over other lifeforms be consistent? What do you think?

Convergent evolution.

In real life, somewhat, but depending on what family they have evolved from. Foxes for example are a case of convergent evolution that fills essentially the same niche as the smaller felids, but they are of the canine family.

if the selection pressures are similar and the organisms are not to different then often.

There are two branches of lizards one in Australia and one in the SW US the look alike and are ant-obligate feeders, but are unrelated.

The US ones are Horney toad or Horned lizards

Yes and No.

Certain body plans and designs fit an environment for basic reasons of physical law. That is why penguins (birds) have a very similar body shape to porpoises and dolphins. Foraging in the water favors a certain hydrodynamic streamlined shape.

The wing has evolved several times in reptiles, birds and mammals. There are two underlying dynamic issues. 1. Heat reduction and retention and 2. aerodynamic lift. This is the basic physics at work.

If we were to "rewind" the cosmos and let it run over again, we would probably not end up with the same biological details due to evolution. Why? There are many chance factors at work. But certain designs will emerge and re-emerge because of the underlying physics....

You can have localized "optimum" solutions--once you get there you won't evolve to the other solutions unless there is a "global" reset.

Look at the body plans of penguins and dolphins. Do you see the similarity?

in some areas, it will.
fish will indeed get the same shape when you reboot evolution on earth, but mammals can be a lot different; perhaps humans would still have their tail, perhaps dogs would be the ones to develop intellligence first.

Biological beings that live in the sea which acquire the shapes which enable them to move through the water with the least expenditure of energy. But that is a very general trend. In the minute details evolution is not completely deterministic. There is a random or chance factor at work. But in the main, the physical nature of the environment will determine the rough outline of the result. Marine biota will be streamlined. That is why penguins (birds) have a similar shape to dolphins (sea dwelling mammals).

https://en.wikipedia.org/wiki/Automobil ... oefficient
The boxy Nissian cube has a surprisingly low coefficient of drag of just 0.35

About the same as my Scion XB

computers cannot evolve. The code is strictly limited to the programmer. By 'evolve' they are actually referencing the computer's default function to resort to it's other gambit codes which were being unused until they were evaluated mathematically, through math which was programmed into the device, to overcome the barriers it had set before it or was setup against. It is an inaccurate use of the term evolve. Computers are strictly limited to the programming, and do not generate alternative codes to overcome new obstacles.