Evolution through natural selection is the process by which organisms change over time. The changes allow an organism to adapt to an environment, survive, and reproduce. Evidence from a wide range of disciplines including geology, genetics, paleontology, and developmental biology support this theory. While the evidence behind the general theory of evolution is overwhelming, scientists do not always fully understand exactly how the process unfolds.
Many laboratory models of evolution have ended with one dominant species that no longer changes to compete in nature. In reality, this is a contradiction of the theory of evolution which is a continuous process that never actually ends. Due to external pressures, newer species will always emerge even when most conditions remain constant.
“This new model suggests that scientists might have found the best way to represent the actual process of evolution.”
New Models of Evolution
A team of scientists from Saarland University in Saarbruecken, Germany has created a new model of evolution that tells a different story.
Because molecular systems are a critical component in speciation, their model uses linear DNA polymers set at different lengths, and the length of the DNA polymer determines its species. As species, polymers can reproduce and create polymers of the same length or join to form longer polymers, which represent new species.
To create the evolutionary simulation, researchers started with polymers, 10 or 20 base pairs long, and exposed them to temperature variation. Temperature change led to the emergence of polymers of different lengths. Because the length of the polymer represented a new species, temperature change in the model resulted in the emergence of new species.
The joining process of the polymers is a growth mechanism, resulting in the formation of all possible polymer lengths. Reproduction served as the other mechanism for growth, and in this experiment, scientists found that it only led to the appearance of certain lengths of polymers and for a limited period.
Over a period, a particular polymer length dominates before reaching a plateau and then a decline, before a new length emerges. This pattern in reproduction dominant situations is similar to Darwin’s theory of evolution.
The periods of polymer length dominance represent an epoch when certain species dominate due to favorable conditions. Saarland researchers assert that dynamics of an entire system that selects a particular, new species or length of polymer in such a way that it can efficiently multiply using the present situation. Despite this, each time, the system avoids a species’ dominance by forming new species that take advantage of the new situation.
This new model suggests that scientists might have found the best way to represent the actual process of evolution.