Marine biologists are studying stickleback fish populations. There are two distinct variations in the sticklebacks based on phenotypes. They are found with the three spines more commonly in marine ecosystems while they are more commonly found without the three
spines in freshwater ecosystems. This has been observed in many marine and freshwater ecosystems across the globe. What explains
the variation seen in the image here across different aquatic ecosystems?

(select all the correct choose each statement that is scientific. - the opinions of randomly selected participants in a survey prove the idea that global temperatures are not increasing on earth. - the universe's average temperature and rate of expansion support the idea that it began as one super-dense and hot mass 13.8 billion years ago. - ocean tides are caused by the uneven gravitational pulls of the moon and sun on different parts of earth. - human life is more valuable than other forms of life on earth because humans are more intelligent than other organisms.