Complex natural phenomena typically have a size window that the laws of physics allow them to operate in, where the processes required for them to occur dominate.

Cyclones are caused by a variety of atmospheric phenomena that result in stable areas of rotating fluid. The smallest cyclones are tornados and waterspouts, which exist on a scale of 2 km (if you include the atmospheric formations that generate them). The largest known cyclone (technically, an anticyclone) is Jupiter’s Great Red Spot, maxxing out at 40,000 km in diameter. 4 orders of magnitude seperate them.

The same goes for galaxies. The smallest galaxy yet found is Leo T, a dwarf galaxy only 600 light-years in diameter. On the other end of the spectrum is IC1101, a cD type galaxy over 6 million light years across – 4 orders of magnitude larger.

Stars, luminous balls of plasma powered by nuclear fusion, also have scale limits. The lower end is around 75 Jupiter-masses, the minimum amount needed to generate nuclear fusion. OGLE-TR-122b, the smallest yet discovered, is around 100 jupiter masses, 166,800 km in diameter. The largest is VY Canis Majoris, at 3,614,000,000 km in diameter. Once again, the difference is 4 orders of magnitude.

Replicators, on the other hand, stubbornly push the boundaries imposed by the laws of physics. The smallest organism is the Mycoplasma genitalium bacteria, at a mere 200 nanometers in diameter, or 1/5,000,000th of a meter. The largest organism is the Giant Sequoia, which can grow nearly 100 meters in height. 8 orders of magnitude seperate the largest and the smallest, an enormous window to operate in. (You can in fact go larger or smaller by pushing the boundaries of what you classify as an ‘organism’.)

There are, of course, enormous selection effects at work here – it’s much easier to measure phenomena on Earth than phenomena anywhere else in the universe, so it will naturally be catalogued much more thoroughly. Nevertheless, the basic machinery of life (ATP energy source, DNA encoding for proteins, cellular structure) has adapted itself to an enormous space of possibility, one larger than almost* any other complex phenomena yet discovered.

*The only exception I can think of is black holes, which can grow without limit due to gravitational effects dominating at large scales.