Thank you for the question of the animal kingdom before the Flood, “Is it possible that the world before Noah’s flood would have been a truly terrifying world to live in with human size, insects, large mammal predators, dinosaurs, and the Nephilim?”
I do not believe the animal or insect kingdom were terrifying to humans. As I read the Genesis account, God brought the animals and insects to Adam to name them. This would include the animals of Jurassic Park. However, the Scripture declared that the animals were tame and vegetarians.
Genesis 1 says this, “Then God said, “I give you every seed-bearing plant on the face of the whole earth and every tree that has fruit with seed in it. They will be yours for food. 30 And to all the beasts of the earth and all the birds in the sky and all the creatures that move along the ground—everything that has the breath of life in it—I give every green plant for food.” And it was so.” (A searchable online Bible in over 150 versions and 50 languages).
Man and animals had no fear between them soon after the Fall, but with each succeeding decade/century the animal kingdom began to change. As man hunted and killed animals, the remains of those animals were eaten by insects, birds, and animals. It is likely insects and animals acquired taste of animal flesh or even human flesh that were killed. It may have been through natural events or through human killing of animals. Exactly when insects and animals began to prey on each other is unknown. Probably the first 100 to 500 years, some animals became meat eaters. With the kindness of man to each other became more and more violent, I would imagine humans feared other humans more than animals.
As we look at the past few months of protests and riots, can you imagine a world back then without civil law except for the laws made by that person over a people group, no law enforcement of any kind, and everyone did what they thought what was right in his/her own eye and we are seeing a fraction of what it may have been like before the Flood. The weak and poor were dominated by the strong and the powerful. The one who had the greatest might rule that territory that may well included the Nephilim. It’s the bully that controls others. The animals learned not to get too close to humans for they might become meat for them.
SUMMARY: Kindness began to die being replaced by the survival of the strongest. That is true then and is true even today. If one is too kind, one will likely be trampled over by others. Love your neighbor became rule over your neighbor. It’s the neighbor that one has to watch, not the animals!
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