In early April, I was fortunate to visit London, where my youngest daughter and her husband, who was studying for one semester, resided. One of my most worthwhile activities during this vacation was a visit to the Natural History Museum, which boasts a collection of 20 million insect and plant specimens and research center. Exhibits abound with taxidermy-prepared birds, mammals, fish and reptiles; and butterflies, beetles and spiders in the thousands. The most popular displays are the life-size, 100-foot blue whale and 50-foot whale skeleton both hanging from the ceiling. Fossilized remains of a dozen different dinosaurs like triceratops and diplodocus were displayed. Upon leaving the dinosaur hall, one is greeted by a life-size, 30-foot long automated model of the dinosaur, Tyrannosaurus rex, which opened its mouth revealing huge sharp teeth when it roared.
The British have a deep pride in Charles Darwin, a fellow Englishman and the father of evolution science, so understandably developed outstanding museum exhibits explaining evolution concepts which I studied and photographed. A series of exhibits compared the large skull and brain size of modern man to the smaller chimpanzee and gorilla brain. Exhibits compared skull and brain size of modern man to extinct prehistoric human-like individuals such as "Lucy," a three-foot-tall upright walking individual from Africa, and to the Neanderthal man from Europe whose skull and brain size equaled modern man. Current knowledge traced human ancestry back two million years, but a precise link between prehistoric manlike creatures and modern man has not been found yet. All these numerous prehistoric ancestors of man discovered by paleontologists have become extinct. Also, plant and animal species that lived millions of years ago became extinct as revealed in fossil records. Present day plant and animal species adapted to changes in the environment allowing them to survive today.
Scientists feel modern whales and dolphins, ocean living but air-breathing mammals, evolved from land animals. One special exhibit captured my interest because it demonstrated convincing evidence of this transformation of modern whales and dolphins from land mammals. I was troubled by the fact that whales and dolphins breathe through nostrils called blowholes on the top of their head. How could a hole on the top of the head of these mammals evolve from ancestors with nostrils at the end of their snout like a dog? This development seemed incredible. Casts of fossilized skulls of extinct mammals on display at the museum demonstrated backward migration of nostrils to the middle of the snout of one animal. Eventually the nostrils developed between the eyes of another mammal and finally developed behind the eyes on top of the skull as in present whales and dolphins. The evolutionary advantage of breathing from the top of the head allowed these ocean animals to keep their head under water, affording them the ability to see and hear sounds of approaching predators or of proximity to available food while breathing. This I found amazing.
Arrows on this museum exhibit of casted mammal skulls point to the nostrils at the end of the snout of the skull on the left, to the nostrils in the middle of the snout on the middle skull, and to the nostrils on top of the head of the skull on the right. The last skull represents the dolphin.
Photo by Robert M. Ungerer
The diversity of plant and animal species on earth is simply mind-boggling. How could such a variety of life occur when biologists assume Earth was a mass of gases and water four billion years ago? Evolution is the story of progression from no life on earth to creation of bacteria, coalescence of one-celled organisms and eventual emergence of animals on land including humans capable of visiting the moon. Scientists consider Darwin's discovery of evolution to be the greatest scientific achievement of all time. The frequent quote, "Nothing in biology makes sense, except in the light of evolution," by Theodosius Dobzhansky, a biologist, bears our thought.
The author Hilma Wolitzer, in her book "An Available Man" (2012), which I read for fun, notes that while man worries about his personal survival, he fails to realize that most species that ever lived before him became extinct because they did not adapt to a changing environment.
Today, we can hope the big brain of a human being will devise ways to adapt to present and future changes in our environment to assure survival.