Stephen Buranyi missed some important points in his article. Darwin saw novel speciation as a result of natural selection but that simple skeleton needed to be fleshed out. It took a century of research to understand the importance of inheritance in small populations.

There are many problems in understanding evolutionary change. We don't yet have a full understanding of how normal embryology works, so it's difficult to work out how the different types of cells form. There are at least four reasons why zebra stripes would be a good choice. The fossil record shows how slow evolutionary change is. Even though modern genetics and systems biology show that heritable novelties can form more quickly than they realise, Buranyi still talks about this topic.

There can't be a unifying theory because evolutionary change involves the complete scale of nature. It's difficult for scientists to convince experimentation. Professor Jonathan Bard is from Oxford.

The biologists who want to modify the theory in the direction of the extended Darwinian synthesis need to go further. All living things are purposive. The ultimate goal for them is survival and reproductive success.

The future course of evolution can be influenced by purposive actions. The future course of evolution can be influenced by purposive actions that result in living in a new environment or pursuing new food. rabbits are better able to escape when they are hunted and foxes are better able to catch them when they are escaped.

When animals make discoveries and learn from one another, cultural evolution can become possible, and that can have a huge impact on the evolution of language.

The purposive actions of living things are important in evolution. Too many biologists have denied the Darwinian role of purposive action in evolution for fear of committing Lamarckism. Chapter 6 of my book Our Fundamental Problem: A Revolutionary Approach to Philosophy gives more information. Science and technology studies at University College London.

There is no reason to have conflicting theories of evolution. The fittest will eventually die. Pete Bibby is from Yorkshire.

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