For some reason people consider being called an animal insulting. Calling someone an animal is a kind of moral judgment, that animals are beneath us civilized human beings. Religion has tried to distance us from animals by creating words like 'soul' and deeming that animals don't go to heaven/limbo/hell when they die - that animals can't think, communicate... whatever... as we are somehow not like them - that we are different. (If there is a real difference between us and animals it is we use money and will destroy our environment to get it - money is useless outside of human society.) Yet increasing evidence shows that we share much with our closest primate relatives, consciousness (imo dreaming probably appears when animals have enough brain matter to support consciousness) appears to be a kind of continuum between us and other animals; and other animals communicate, use tools, have rituals and innovate just as we do and ultimately live in hives or pacts just like we do. Nevertheless the reality is we are a kind of animal. And not being able to admit it speaks to it's denial.
Google defines mammal as "a warm-blooded vertebrate animal of a class that is distinguished by the possession of hair or fur, the secretion of milk by females for the nourishment of the young, and (typically) the birth of live young."
In classical deductive reasoning - if you happen to be offended by the notion of being an animal:
all mammals are animals
human beings are mammals
therefore human beings are animals
There are some truths that come with our mammal/animal nature, we are born, we eat & drink, we have sex to procreate, we sleep, we come with a body that we have to care for, we get sick, we use the bathroom (another thing we seldom discuss) and we will die.
In the course of my years I have only ever seen one dead body. It's not like I haven't been to funerals, I have been to many and I have known lots of people who have died but all but one of those bodies society protected me from.
I gave my husband Doughty's book to read and he said as a man he could go for years without seeing blood. Being alive is different for women, every month we are reminded we are alive by our menstrual blood - something that we must not discuss and pretend doesn't happen because I think it reminds society that we are animals.
Being protected from our animal nature also hides babies and children from society, older people, the sick and disabled are also hidden from us. All those things that remind us we are getting older and our bodies are fallible.
Our animal/mammalian nature is bound to our fear of death, our fear of the unknown and what will happen next - once we die.
I have often thought that our fear of death springs from our fear of being left out - that there will be an on going party and once we are dead we're no longer invited. And part of that is that we will be forgotten. That those who are at the party will go on to forget about us because we won't be there to remind them that we existed. But there are other reasons too - like not being here to be able to help those we leave behind. If you are afraid to die then you might have other reasons.
I am not sure if we are afraid of death because it reminds us we are animals or whether we are afraid of acknowledging we're animals because it reminds us we will die. Either way, the universe recycles everything (just like our environment recycles everything) especially our bodies - if being alive is distinct in some way from our functioning body - it would seem that our life too would be recycled. Besides there are plenty of anecdotal stories of reincarnation and ghosts, I can't believe that all these people decided to lie about their experiences.
Doughty wrote an important book - I recommend reading it just to know what to expect - so you can be prepared when someone you love dies.