“I am inclined to believe that in nearly the same way as two men have sometimes independently hit on the very same invention, so natural selection, working for the good of each being and taking advantage of analogous variations, has sometimes modified in very nearly the same manner two parts in two organic beings, which owe but little of their structure in common to inheritance from the same ancestor.”
Charles Darwin, The Origin of Species
To put Darwin’s statement in other words, it looks very much as if the processes of evolution have hit upon the same solution multiple times. Continue reading →
Imagine two people from two different tribes, separated by space or time, coming up with the same idea or way of doing something. If it is a good invention it will surely spread within each of their families and communities. Is this a coincidence, or would it make more sense if Continue reading →
Last weekend, the Faraday Institute ran a course on ‘Science, Religion and Atheism’. The aim was to examine questions of science and religion from both theistic and atheistic positions. The speakers were more than usually candid about their own views, which was both refreshing and a fascinating sociological exercise. (See the Faraday website for recordings when available).
To continue last week’s theme of biology raising questions that in the past have been left to cosmologists, I will focus on Simon Conway Morris’s presentation at the course. I have already written on biochemical fine-tuning but the related theme of convergence, which is the focus of Conway Morris’s research, is also an important one.
Simon Conway Morris is one of those thinkers who prefer to limit themselves to the most risky fields of investigation. He is genuinely interested in upsetting the applecart of received dogma, and getting closer to the truth. As a PhD student, Conway Morris worked with Harry B. Whittington on the Burgess Shale in British Columbia, and was part of the huge revival of interest in the Cambrian Explosion.
At first the Burgess Shale fossils seemed to point to the randomness of the evolutionary process – a point that Stephen Jay Gould elaborated on in his book ‘Wonderful Life’. It has become something of a convention in the biological world to avoid using teleological language, and Gould famously suggested that if you ‘reran the tape of life’ you would get something completely different. That strikes at the heart of who we are, and the theological consequences are enormous. Is the existence of human beings a happy accident? How could people of faith even consider evolution if the implication is that intelligent beings such as ourselves are an accidental dot on the cosmic landscape, rather than lovingly created by God?
But as Conway Morris proceeded in his career in palaeobiology it seemed to him that evolution had repeatedly navigated towards similar solutions in different contexts. An example of this is the sabre-toothed cat. In North America this deadly cat was a placental mammal, and in South America it was marsupial – sabre-toothed cats evolved at least twice. Other examples include the ‘camera eye’ that has evolved many times independently, and the octopus’s tentacle that bends in a similar manner to a jointed arm.* The conclusion that can be drawn from the vast number of examples of convergent evolution is that there seem to be a limited number of ways of solving the same problem. One could describe these solutions as points towards which evolution navigates. So if you reran the tape of life, the emergence of intelligent beings like us might actually occur every time.
In his seminar Conway Morris took his thesis further, speaking about extraterrestrial intelligence, consciousness, and language. The fact that we can see beyond the limits of our inbuilt sensory systems, and have capabilities way beyond any other animal species has prompted many to ask questions about humanness that sound like religious questions. I realise that this is a vague theological ending to a largely scientific piece, but Conway Morris is often tentative in his theological conclusions. Hopefully another book is on the way that will take this line of thinking further.
*You can see these and many other examples of evolutionary convergence at mapoflife.org.