There is good reason to believe fish, amphibians, molluscs and insects are sentient, according to a new declaration signed by three dozen scientists.
The New York Declaration on Animal Consciousness argues that current scientific research indicates such widespread animal consciousness is a “realistic possibility” — and that scientists and policymakers must take that into account when considering risks to those animals.
One line of research has followed the increasing evidence of self-awareness in fish and reptiles. Reptiles, in particular, are ancestral to both mammals and birds, the two orders for which there is the strongest evidence of sentience.
Like jumping spiders are a great example of insect intelligence. They even show signs of experiencing dreams, such as rapid eye movements and twitching whilst resting.
I have both a pet jumping spider and a pet lizard, and both show obvious signs of having intelligence and distinct personalities