Frogs have only one opening, called the cloaca, through which both feces and urine pass. Humans, however, possess two separate orifices for urine and feces to exit through.
Wind, water, light, temperature are all examples
In my opinion, it always depends on the partner how they are going to maintain their healthy relationship.
But for my opinion, here are the top 3 ingredients for a healthier relationship:
1. Communication - it is always important that you and your partner are being open with each other and being honest
2. Trust - trust is one of the most important and essential ingredients of healthy relationships
3. Commitment - how can you be in a healthy relationship if you are not commited?
The answer would be survival of the fittest.
This metaphor, "<em>survival of the fittest</em>," was used by Herbert Spencer to explain <em>natural selection. </em>It is sometimes also referred to as the survival for existence. This phrase came from the Dawinian theory of evolution where he explains that all species are capable of producing many offsprings. However, the survival of those offsprings depends on their ability to adapt to the risks and opportunities of the external environment.
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</em>This relates to your scenario in the sense that fish lay a lot of eggs in the beginning but not all of them would live to achieve maturity. This is because even as eggs, they have many predators and are exposed to other elements. The threat pushes on even if they are able to hatch and grow up.
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The answer is because a part of the organism could die and the organism could continue to live.
In the very changing environment, such was when multicellular organisms evolved, the organisms that could adapt to that environment, survived. If in some moment multicellular organism emerged and its multicellularity helped him to survive, that is the reason this characteristic remained. On of the explanation is that multicellularity allows the organism to continue to live even if <span>a part of the organism dies.</span>
