Science & Faith pt 2
The diversity of life on earth is amazing. Any trip to the zoo or aquarium, time spent watching Planet Earth, or better yet, any walk in the woods lets you experience a glimpse of the diversity here on Earth. Again and again, I find myself in awe of insects on a flower, the number of ferns in the forest. birds singing above my head, or critters under a log. If you've read my blog before, then you might have figured this out about me already (see posts on taxonomy, salamanders, and warblers). But, have you ever wondered why? Why are there so many different birds, bugs, and butterflies? For goodness sake, why do we need so many different ferns in New England alone that are so similar I can't tell them apart??
This question of life's origins and species diversity is one that men, women, and children have been trying to answer since we shared the Serengeti with secretary birds (maybe don't quote me on that). Artists, philosophers, scientists, and theologians have all pondered this question and offered their opinions, but, what kind of question is it? Whose answer should we go with? And, how do we know if we are right?
Last week I introduced a series of posts running alongside a course exploring the intersection of science and faith at my church. In part one I wrote about the roles and limitations of these "two books." If you haven't read that yet you can catch up here. In this post we will explore earth's biodiversity, how we explain it, and what happens when we take those explanations too far. I hope there are lots of pretty pictures of cool plants and animals...
Thousands of years ago, the Greeks had surprisingly modern scientific and philosophical ideas - even when it comes to origins of species. Anaximander, an early Greek thinker, decided based on his observations of fetal that all life had originally sprung up from the sea. A few centuries later, Aristotle believed that all life was ordered in a perfect and fixed "Scale of Being" from inanimate objects on the one end all he way up to deities on the other.
After the Renaissance and Enlightenment revolutionized science and learning in Europe, thoughts about life and origins of species began to change as well. A lot of thinkers and scientists contributed ideas all over the world from Aristotle into the modern era, helping to iteratively shape a revolutionary scientific theory. As modern science began to take hold in the 16th and 17th centuries there were several key turning points in the evolution of thought on earth's diverse life. One key contribution came from a Frenchman named Georges Cuvier (1769 - 1832).
Born in 1809 in Shrewsbury, England, the works of Charles Robert Darwin published about 50 years later would revolutionize biology. Now a seminal figure in the history of modern science, Darwin began his career studying Divinity at Cambridge, while there he devoted himself to diligent natural observation and science in his free time. Upon graduating in 1831 Darwin was offered the opportunity to join the H.M.S. Beagle as a "gentleman naturalist" as it sailed around the world. While aboard the Beagle, Darwin was reading the newly published Principles of Geology as he soaked in the globe's astounding biodiversity and pondered the ideas of men like Lamarck with the added benefit of Lyell's extended geologic timeline.
The Beagle spent a good amount of time on the Islands of the Galapagos. While there, Darwin noticed a curious group of finches, each one possessing a uniquely adapted bill to exploit a food resource on the island. Darwin also recognized that while these birds appeared similar to the finches he had observed on South America's mainland, each was a distinct species. Upon further observation, Darwin proposed that sometime in the island's past, one species of finch colonized the island and over time diverged into several different species.
The proposed method for the Darwin's 'many finches from one' hypothesis was natural selection. Natural selection is the process by which certain inheritable traits allow some offspring to survive and reproduce better than others (this is an awesome video on natural selection). As Darwin observed natural populations, he noticed that like the captive fancy pigeons he raised, variation exists between individuals. And, he saw, that some of that variation was heritable, and improved an individual's chances for survival and reproduction, making it more "fit." Over time, as the best adapted individuals had more offspring and passed on their traits the population as a whole would become better adapted to the environment - natural selection at work! Overtime, as these small variations and adaptations add up a population can become a distinct species.
There are countless other examples of evolution in action. From convergent evolution between marsupial and placental mammals, transitions from dinosaurs to birds, and the return of whales to the sea. Darwin's theory of evolution via natural selection gave a clear, precise, and testable mechanism that explained how species arise, and critically, why so many different species exist! Species arise through selection and adaptation to exploit resources and do "jobs" in the ecosystem!
Science out of bounds?
I've just spent a while talking about Darwin's evolutionary theory, what it means, and how the idea itself evolved. We know, through countless observations in nature, the fossil record, and experimental tests, that species change through the process of natural selection and evolve over time to new species.
As evolutionary biologist and Eastern-Orthodox Priest Theodosius Dobzhansky once famously wrote "nothing in biology makes sense except in the light of evolution." But can evolution be take too far?
As I discussed in my last post, the "book" of science deals only with the natural and physical aspects of the universe. Origins and evolution of species clearly falls within this book, but in the past 100 years many have sought to look to science, objectivity, and evolution to explain all aspects of the universe, physical and meta-physical. Richard Dawkins is perhaps the most vocal modern tenet of this belief system - Evolutionism. Evolution may be able to explain the biological and evolutionary origins of cultural norms, but can (or should) it decide what is and isn't the "right" thing to do?
Taken one step further, it is true that evolution through natural selection does not require a divine being in order to function, but simply the fact that a supernatural being is not required cannot prove it does not exist. Because god (by our working definition at least) is supernatural, he/she exists above or outside of nature, and therefore cannot be proven, or disproven by scientific methods! Said simply, when science, objectivity, and evolutionary thought are used to prove or disprove god, establish ethics and morals, or to unlock life's purpose, it is overstepping the bounds of the Two Books framework.
Next up - Religious Origins and Religion out of Bounds
Science is not the only Book that can overstep its bounds! In my next post we will talk about how religion (specifically Christianity) actually explains origins, and when religion is taken too far, stay tuned.
As always, don't forget to subscribe to get email updates whenever I post, and please leave a comment below. Over and out!
References and Recourses
Larson, Edward John. Evolution: The remarkable history of a scientific theory. Vol. 17. Random House Digital, Inc., 2004.