The shift towards agriculture and animal husbandry, also known as the Neolithic revolution, allowed for the development of larger, more complex societies and the rise of cities and civilizations. It also led to significant changes in human diet and lifestyle, as people began to rely more heavily on domestic crops and animals for food. But not all of human population made this transition at the same time or in the same way, and some societies continue to rely on hunting and gathering even today. Additionally, it is also worth noting that while the Holocene epoch began around 11,700 years ago, the Neolithic revolution and the transition to agriculture did not happen uniformly around the globe and took place in different time periods and locations.

Yes, animals that consume infected birds can become infected themselves. However, many scavengers, such as vultures and other birds of prey, have a relatively high resistance to avian influenza and may not be affected by the virus or die from it. Additionally, the virus may not survive well in the animal's body, and therefore would not be able to infect others. Many domestic animal like pigs, cats and dogs have a different type of receptors in their respiratory system, which makes it harder for avian flu to infect them, as it is not able to bind to those receptors.

When wild birds are affected by a disease, they may die in areas away from human populations, such as in remote wetlands or forests. Additionally, scavengers such as other birds or mammals may quickly consume the dead birds, making them less likely to be seen on streets or in other urban areas. In some cases, birds that are sick may also hide or isolate themselves, making it less likely for them to be seen before they die.

It's actually pretty complicated, but in general, viruses need certain receptors on cells in order to be able to infect them. These receptors are usually specific to certain types of animals, which is why you can't just give a virus to any animal and expect it to be able to infect them. Additionally, even if a virus is able to infect a certain animal, it may not be able to replicate effectively or cause disease, which is why a lot of cross-species transmissions don't result in an outbreak. In short, it's all about the virus's ability to bind with specific receptors on host cells and replicate effectively.

When a radioactive substance is touched or consumed, the radioactive particles release energy in the form of ionizing radiation. This radiation can damage or kill cells in the body, leading to various health effects depending on the amount and duration of exposure.

At the cellular level, ionizing radiation can damage DNA and other cellular structures, leading to mutations and cell death. This can increase the risk of cancer and other diseases. The brain and nervous system can also be affected by ionizing radiation, leading to cognitive impairment and other neurological effects.

Our body does not naturally build a defense mechanism against ionizing radiation.

The lifespan of a species is determined by a combination of genetic and environmental factors. Genetic factors include the presence or absence of certain genes that are associated with aging and disease, while environmental factors include access to food and water, exposure to toxins and pollutants, and susceptibility to predators and disease.

Humans have a relatively long lifespan compared to many other species, including housecats, due in part to genetic factors such as the presence of telomerase, an enzyme that helps to maintain the integrity of chromosomes and therefore the longevity of cells. Additionally, humans have a relatively low rate of predation and access to medical care and other forms of protection from disease, which also contribute to our longer lifespan.

Early human life expectancy was ably about only 20 years too.