Metcalfe’s law, which states that the value of a network grows with the square of its number of nodes, is a mainstay of telecommunications theory. But it also relates to biology because the web of life is a network, too. Each passing year brings to light new varieties of interconnections and relationships among the ever-widening diversity of organisms, cells, genes and biomolecules known to science. Because of evolution, we can see how the web of life also extends back through time, with genomic connections that link very different organisms through common ancestry. We have a deepening understanding of the mathematical principles that govern how all of Charles Darwin’s “endless forms most beautiful” survive, adapt, multiply and thrive.
In 2018, researchers gained useful insights into the genetic collaborations that produce living cells and into the recesses of life’s genomically tumultuous past. Viruses are starting to look less like parasitic, quasi-alive offshoots of “real” cells and more like a crucial component of life itself. Many hidden talents shared by complex cells are also becoming more apparent. And although we are far from truly understanding the most intricate and powerful biological network of them all — the brain — neuroscientists made some meaningful progress in understanding aspects of cognition and memory, among many other accomplishments.