For several months now, as the swamp wallaby decayed, I waited for this moment. Its flesh was eaten by the earth. The skin facing the sky dried in the sun. An ear and some skin remains attached to the skull. I swallow hard and sweep aside the last small beetles crawling about. Then I look into its eyes.

Or rather, into the space for its eyes. Seven different bones, each made for other purposes, create eye sockets. The larger ones house the brain, frame the cheeks and hold the teeth of the upper jaw. All share an edge which together makes the orbit, the housing for eyeballs. In there, I can see memory.

There is the immediate memory of the animal who grew from tiny egg to an adult of maybe some fifteen kilograms. Part of his material life was a process that filled connective tissue with minerals and created these hard bones. Another part was his sustenance and work as a plant eater, trimming bushes and shrubs as well as digging up edible fungi. In his role with other animals, he was a marsupial mate, parent, ally or prey.

Now, for me, he is a catrina doll. He’s an artwork in the old Mexican tradition for the celebrations on the first of November, the Day of the Dead. Or the Christian All Saints Day or All Souls Day, the Celtic Samhain or the secular Halloween. During this observance, I want to remember the animals that died.

Population statistics report that 137,900 humans died in Australia last year. So did over three million farm animals and around 250,000 dogs and cats at animal shelters. Of fish and shellfish, not considered individually, 50,000 and 65,000 tonnes. The discarded by-catch, according to WWF, is 40 per cent more.
The best estimates for animal deaths due to land clearing across Australia is data from 1997-99: a hundred million. For every hectare of land that is modified, deaths average 223 mammals, birds and reptiles. The numbers that die in existing modified habitats are unknown. Is there a clue in road kill statistics? Based only on Tasmanian data, an average of 32 animals die each hour.

Surely there are animals that die natural deaths. Was this wallaby one? But these others listed are all our doing. As animals ourselves, in staying alive, we are bound to kill. But what requires of us to kill more than that need? What size is that need? If we must, how to kill humanely? And how to avoid killing at random? Can we set standards?

One approach is to bring into law ethical considerations based on scientific evidence. In 1824, Richard Martin and William Wilberforce, founders of the RSPCA, also battled for the first animal welfare legislation in the UK. Although the law was ridiculed at the time, many countries now accept that standards for the care and killing of animals are important. Despite ongoing derision, higher standards continue to be debated and legislated: the lifestyles of farm animals, slaughter practices and more. Standards now extend to wildlife as well.

New evidence, new campaigns. Since 1994, the Great Ape Project, led by Jane Goodall and ethicists Paola Cavalieri and Pete Singer, lobbies for basic legal rights for non-human great apes. This year, marine researchers Lori Emory in the USA as well as Wade Doak in New Zealand call on nations to grant moral personhood to whales and dolphins.

These are straightforward tangible legal goals. After all, since 1869, the same has been granted to imaginary beings such as corporations.

With our formal laws, we set out our own minimum best behaviour with animals. Weighing up the skull in my hand, I wonder what is our very best.

We think we know animals. But in 1944, Donald Griffen first showed how bats manoeuvre in the dark using unimagined sensory skills that he called echolocation. In 1986, Scheich and his team proved that the platypus hunting underwater closes its eyes and ears and uses its bill. This has a sixth sense, known as electroreception. In 2005, Holy and Guo found that in the ultrasonic, well outside of our hearing range, mice, like birds, are singing songs.

Sometimes, I stand quite still in the grass or forest and get poesy. Animals are here. They exist in fabrics of movement, deep in perfumes of touch and taste.

Using kaleidoscopes of sounds, acting on subtle cues, they orientate in dimensions of which we can only guess.

In 1971, Krause analysed the very soundscape in undisturbed natural environments and found that each species of animal uses different frequencies.

Calling and listening, they are all tuned to the original in community broadcasting.

Whatever animals make of us, we must seem disruptive, noisy and warlike. We break all the laws they know. But we are experiencing repercussions delivered by contaminated meat, polluted waterways and more. As we wear out domestic and wild animals by endlessly disrupting them as well as deafening them with noise of every sort, we too are getting sick and going deaf.

Perhaps our best is our humblest. The blood of many, many animals and humans was spilled to bring us all to this junction of hurt and understanding.

Hold this memory. Using what senses we still retain, looking outside of our bumbling selves, could we once again be learnable?

For more by Mary Gardner about animals and biodiversity, check her website Tangle Of Life www.tangleoflife.org.