What can be measured and what cannot · Chapter 4 of 4
The Orca Who Carried Her Calf
On seventeen days, a thousand miles, and the limit of what can be known.
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In the summer of 2018 a southern resident killer whale known as J35, or Tahlequah, gave birth to a calf that died within about half an hour.
She did not leave it. She carried the body, pushing it at the surface, for seventeen days, across roughly a thousand miles of ocean. A calf's body does not float; keeping it up requires continuous effort, and while she was doing it she could not hunt normally. Members of her pod were observed nearby throughout. On the seventeenth day she let it go.
The behaviour was documented by researchers who had been following that population for decades. It is not in dispute.
What she experienced is not accessible, and the careful literature says so directly.
Similar behaviour is well recorded elsewhere. Elephants return to the remains of dead relatives, sometimes over years, and handle the bones. Chimpanzee mothers carry dead infants for days or weeks, continuing to groom them. Corvids gather around dead members of their own species. The observations are consistent, repeated and cross-species.
Here is the argument that gets us as far as the evidence allows, and no further.
The behaviour is expensive. Tahlequah could not feed properly for more than two weeks, in a population that is already nutritionally stressed and endangered. Carrying a dead calf offers no benefit that anyone has been able to identify. Behaviour that is costly, sustained and useless is difficult to explain as a reflex or an error, because reflexes and errors are usually cheap and short.
So something is happening that matters enough to the animal to outweigh feeding, for seventeen days. That is a real conclusion, and it is narrower than the word grief.
Two errors are available here and both are lazy in the same way.
The first is to read a human interior straight into the animal, to describe her as heartbroken and to write the story as one you already know. The second is to say that because nothing can be verified, nothing is there, and to treat the behaviour as an automatic response that happens to look moving.
Both replace an open question with a comfortable answer. The first is comfortable because it makes the animal familiar; the second because it makes the problem go away.
The philosophical background is Thomas Nagel's question about what it is like to be a bat, which this library teaches elsewhere, and the structure here is identical. We have excellent third-person access to what an orca does and no access whatever to what it is like to be one. No improvement in instrumentation changes that, because the gap is not a gap in measurement.
What is left is a discipline rather than a conclusion. State what was observed. State what the observation cannot reach. And if you are going to go further, which most people will, say out loud that you are making a choice rather than reporting a finding.
That is the whole method of this book, and the orca is where it is hardest to keep.
We can measure what she did for seventeen days. We cannot measure what it was like.
Where you'll meet this
Two errors are available and both are lazy: assuming an animal feels exactly what you would, and assuming that because you cannot verify it, there is nothing there.