DEAR DR. FOX: This will always be my favorite quote because of the truth of it. It is from Albert A. Bartlett (1923-2013), professor of nuclear physics at the University of Colorado: "Can you think of any problem in any area of human endeavor on any scale, from microscopic to global, whose long-term solution is in any demonstrable way aided, assisted or advanced by further increases in population -- locally, nationally or globally?" -- V.L.C., Wellington, Florida

DEAR V.L.C.: Precisely said! Regrettably, we are in a situation now with millions of environmentally, economically and politically disenfranchised migrants and refugees.

The U.N. Biodiversity Conference in Montreal last month, also known as COP15, succeeded in securing nonbinding agreements from close to 200 countries to protect 30% of terrestrial and aquatic ecosystems by 2030. Signatories agreed to take steps to halt species extinctions, protect 30% of the planet for nature, restore 30% of degraded ecosystems and reform $500 billion in subsidies that encourage environmental damage. (Full story: CNN, Dec. 19; The Guardian, Dec. 19)

The main drivers of environmental destruction identified at the conference were agriculture, overfishing, logging, mining, climate change, invasive species and overall pollution. But missing from this list, at least to my knowledge, is the issue of population growth. The human population is now being estimated at 8 billion.

Perhaps this omission was a combination of amnesia, denial and politics, but the fact remains: Humans are the most invasive and destructive of all species. Many COP15 delegates and attendees were not even born when this issue was first raised by the Club of Rome's first report, "Limits to Growth," published in 1972. Widely publicized to world leaders and governments, the report showed that economic growth could not continue indefinitely because of resource depletion. It underscored that economic growth meant greater environmental impact, and that the main path to environmental restoration was the reduction of both population and consumption.

But now we face what scientists and conservationists call the sixth mass extinction: the Anthropocene apocalypse, the severity of which we may still be able to minimize, given the will and the means. Climate change and loss of biodiversity will lead to ever more famines, plagues and pestilences if we fail to act now. For some excellent information, go to sentientmedia.org.

The U.S. government and the Vatican declined to sign the COP15 agreement, and representatives from Cameroon, the Democratic Republic of Congo and Uganda expressed disagreement. The non-signing by the Vatican reminds me of their centuries-long opposition to all forms of contraception other than abstinence -- which certainly helped increase family sizes in Catholic communities around the world.

DEAR DR. FOX: I have a 17-year-old cat who has developed diabetes. Kitty was very healthy and active when I moved to Maine two years ago, but her immune system seemed to collapse when the vets here insisted on giving her an annual rabies shot. I had asked that they be mercury- and aluminum-free.

She is an indoor cat: There are too many ticks here that spread illnesses from Lyme to anaplasmosis. She received some tick bites during the few times we let her outside two years ago. She had no visible reaction to the bites, but I stopped letting her out, even briefly.

She nearly died last year when she first developed diabetes, but she came back strong with a new diet of Wellness brand canned cat food and some frozen raw food containing turkey, salmon, lamb and other ingredients. I give her potassium and minerals as supplements.

Lately she is getting very fussy; she has greatly slowed her eating and is losing weight. She is drinking a lot of water. Do you have any food recommendations to heal her and strengthen her? The vets stopped giving her vaccines because she is now too frail. -- G.C., Harpswell, Maine

DEAR G.C.: Your old cat's declining condition was most likely exacerbated by the rabies vaccinations, which the vet did not have to insist upon since your cat is (now) always indoors. Please note that I am not some antivaxxer, but a veterinarian with 60 years of experience dealing with a variety of animal health and welfare issues.

Diagnosed early, diabetes can be resolved by a change in diet -- essentially, no more high-carbohydrate dry kibble, which many veterinarians are still selling in their clinics.

Lack of appetite is serious for cats, since it can lead to fatty liver disease. Try to coax her to eat several times a day with high-protein foods such as canned sardines in water (watch her closely, as some cats are allergic to fish); shredded, boiled chicken or turkey; or any organically certified meaty baby food you can find. (Another word of caution: Many common baby food brands contain heavy metals and other contaminants not fit for babies or cats!) Or make something in a food processor, perhaps based on my home-prepared cat food recipe, which is posted on drfoxonehealth.com. Adding a pinch of Bragg's nutritional yeast or a small piece of a crushed B-complex vitamin to the food may help stimulate appetite.

My book "The Healing Touch for Cats" may help stimulate your cat's circulation and with gentle, deep abdominal massage, help with digestion and evacuation. Most cats respond very positively to such treatment. Above all, make your cat feel as secure and comfortable as possible.

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

Visit Dr. Fox’s website at DrFoxOneHealth.com.)

DEAR READERS: If you have a cat and want to follow my advice to keep him/her indoors for health and safety reasons and to protect wildlife, you will also want to provide an enriching, physically and mentally stimulating environment. Consider the following elements: A tall and sturdy scratch post is a must, along with a cat tower or elevated platform in the home and a bird feeder by the window.

Adopt an easygoing second cat (see how to introduce them on my website: drfoxonehealth.com/post/introducing-a-new-cat). If you do not yet have a cat and are wanting to get one, consider adopting two, such as littermates or a mother and kitten. Do some research and get creative setting up an outdoor enclosure or "catio." For ideas, visit these websites: catiospaces.com, catioworld.com and adventurecats.org.

DEAR DR. FOX: I enjoyed your article about our fate and the fate of the insects. Check out the website geoengineeringwatch.org, because I think that is also one of the big harms to insects and other creatures.

I have a garden and pond, and I see very few bees. I have almost no frogs, dragonflies or other insects, and there used to be plenty. -- M.G., Anderson, California

DEAR M.G.: Thanks for sending me the information about atmospheric geoengineering in response to my column about the plight of insects.

Humans have been "geoengineering" since the beginning of agriculture with irrigation, plowing the grasslands and felling forests with ever increasing expansion and harm.

I have mentioned this issue of atmospheric geoengineering in earlier columns. I share the concerns of many over the lack of transparency by the agencies spreading various particulate materials, including aluminum, in the upper atmosphere to "shade" the Earth and slow global warming. This could reduce our exposure to beneficial sun rays that boost our immune systems with vitamin D and also kill viruses and other potentially harmful microorganisms on exposed surfaces. Ultraviolet light is recognized as an excellent sterilant. This practice may also reduce crop yields.

Some aerial spraying at much lower altitudes is used to spread pesticides over various crops, and the documented "drift" onto private property and organic farms is a continuing concern.

I am also concerned that this atmospheric geoengineering, which some technophiles like Bill Gates are advocating and funding, could harm the atmospheric microbiome of bacteria and viruses that encircles the Earth, about which we know little. This microbiome could have ecological and potentially life-sustaining and renewing properties.

ANIMAL-ASSISTED THERAPY HAS DEEP ROOTS

Both Sigmund Freud and child psychologist Boris Levinson saw the benefits of bringing their dogs to psychotherapy sessions to calm and build rapport with patients. Samuel and Elizabeth Corson published research on how dogs can enhance psychiatric care. Even Hippocrates promoted horseback riding for mental health. The benefits of therapy assisted by dogs, horses and other animals are now widely accepted. "It is interesting to note that (animal-assisted therapy) can be used multiculturally without the need to adjust how it is applied to different ethnic groups," writes counselor Cody Zaiontz. (Full story: Psychiatric Times, Oct. 12)

I knew the Corsons and consulted with them many years ago, publishing Levinson's review "Interpersonal Relationships Between Pets and Human Beings" in my 1968 book "Abnormal Behavior in Animals." This collection of articles by several experts helped establish recognition and treatment of emotional/behavioral problems in animals and documented their benefits to us along with the ethical obligation of humane treatment and duty to care.

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

Visit Dr. Fox’s website at DrFoxOneHealth.com.)

DEAR READERS: Some animal protection organizations are seeking to establish the legal "personhood" of animals such as elephants, orcas, dolphins and beluga whales -- partly on the basis that they show self-recognition when given a mirror -- in order to get them released from impoverished environments of captivity.

In 1970, psychologist Gordon Gallup Jr. developed a test that he claimed was the cardinal indicator of self-awareness in animals. The experiment involved chimpanzees responding to a mark on their faces when they saw their images in a mirror. It has since been widely cited as indicative of self-awareness in animals. The test has had similar positive results on other species, including the great apes, elephants, rays, dolphins, orcas, Eurasian magpies and ants. But a wide range of species has been reported to fail the test, including several species of monkeys, giant pandas and sea lions. From an ethological perspective, these "failures" reveal the fallacy of psychologizing animals' behavior. In many species, especially humans, positive responses to changes in a self-image seen in a mirror may be no more than an indicator of narcissism.

The Gallup mirror test, now being embraced in legal terms of animal "personhood," is an example of psychologism. It is wrong to assume that those species who fail this test have no sense of self and, therefore, no personhood to warrant equal consideration and protection.

Dogs will often bark or growl when they first see their image in a mirror; they will not respond when a mark is put on their heads, and they will ignore subsequent mirror encounters. Such ignoring surely indicates that they know it is not another dog. Other studies have shown dogs have body awareness and self-awareness in recognition of their own versus other dogs' scents.

A better gauge of the sense of self in relation to objects is the demonstrated ability to count, which is evident in many animal species. Numerical abilities have been identified in gorillas; rhesus, capuchin and squirrel monkeys; lemurs, dolphins, elephants, black bears, birds, salamanders, certain fish, ants and spiders.

And without some sense of self, how could animals, including insects, groom and preen themselves and each other?

In assessing animals' self-awareness, we need to avoid psychologizing and consider each species and its adaptive, cognitive abilities and related environmental, physical, social and emotional needs to make informed, science-based decisions as to their optimal care and protection. For references, go to drfoxonehealth.com/post/animal-sentience.

DEAR DR. FOX: You have written a lot about how empathic and intelligent wolves are. But they tear apart deer and other prey. Isn't that cruel? I hate such predators. -- T.V., West Palm Beach, Florida

DEAR T.V.: Predators provide many ecological services, which ultimately benefit their prey -- and us. (For details, go to drfoxonehealth.com/post/wolves-and-human-well-being-ecological-public-health-concerns). It is true that wolves do not have a quick-killing bite, while big cats like tigers can sever the spinal cord in the necks of their prey and kill swiftly. However, nature may protect deer and other prey from feeling pain, if not also terror, because the attack may trigger numbing endorphins.

While traveling in Africa in 1857, Scottish explorer David Livingstone observed in his daily journal that when he was attacked by a lion, he became numb. He considered the experience an altered state of consciousness, in which he was able to watch the proceedings without feeling the pain.

Scientists have subsequently revealed the release of endogenous opiates (enkephalins and endorphins) in many species, including earthworms and fish, when subjected to traumatic injury. This does not mean that it is acceptable to hook fish and mutilate sentient animals because they may not experience pain, but rather, we must acknowledge that they do react to injuries and trauma as we do and should not be harmed. Sentience goes everywhere from invertebrates to mammals, from earthworms to humans.

This endogenous opiate neurohumoral system, along with oxytocin and other neurochemicals, plays a role in social bonding and empathically and vicariously experiencing and responding to other's suffering. It is evidenced in the behavior of social animals responding to the plight of peers and protection of their offspring. In their review on this subject, "Toward a cross-species understanding of empathy" (published in Trends Neurosci in 2013), J. Panksepp and J.B. Panksepp state: "Cross-species evolutionary approaches to understanding the neural circuitry of emotional 'contagion' or 'resonance' between nearby animals, together with the underlying neurochemistries, may help to clarify the origins of human empathy." Animals witnessing others being slaughtered, therefore, raises a significant ethical issue when it comes to how most animals destined for human consumption are killed.

While some people wonder what kind of God could create a world where there are predators, we learn that one life gives to another to sustain a greater whole. One lesson from wolves is that they help with the balance of nature, preventing deer overpopulation and destruction of shared habitat. We humans break this "covenant of the wild" when we take more than we need, wanting ever more and destroying the whole in the process.

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

Visit Dr. Fox’s website at DrFoxOneHealth.com.)