Moray at Mahukona

We drove to Puako Village yesterday to dive, but the surf was up, so instead we went to Mahukona, our "stormy weather" dive spot here on the Big island. Visibility was about 50 feet in the shallows. We saw an undulated moray that I am sure was over 6 feet long along an old chain from what's left of the freighter wreck there.

Undulated morays are seldom over a meter long, so this was a big, "tiger" one.

On the Context Dependence of Essence

"For you are dust, and to dust you shall return."
--Hebrew Bible, Genesis, 3:19b

In this passage, God speaks very reductively about living humans! Does he say here "you are made of living tissue" or "you are evolved from other animals"? No, people are just terrestrial minerals, which is to say simple inorganic and organic compounds. God looks very much like a reductionist here, if not an outright eliminativist about categories such as life and consciousness. Humans are just rearranged physical stuff, and they return to the basic forms of the same physical stuff, God says here. (And yes, it is also in a very negative context, about human mortality).

So, if God can be a reductionist about human existence in some contexts, why can't we be so also? There are many scientific virtues to considering real substance and essence to be things which are very relative to context.

The human organism is a part of a larger culture, and our culture exists as part of the planet earth. On one level, we are but a part of a whole, life on Earth, which is the substance created in the Genesis stories. On another level, our organs and their systems are the substance, made of cells.

In the past century, medical science has had its greatest successes via investigations which treat animals and humans as systems of organs, not as persons, and not as cultures. This lack of holism can be seen as a limitation of much of current medicine, yet without the reductionist's ability to target substances at the level of the body's systems and organs, most medical technology would fail.

Some of our best diagnostic tests work at the level of organic and inorganic molecules (laboratory science) and atoms (CT and MRI scans). Without considering the body as mere well hydrated, structured dust, our imaging systems could not have been invented.

Pragmatically then, what is a substance? It is whatever form and whatever matter we need to understand in our chosen context. Form and matter are related like layers in a cake: one layer's matter is the next layer lower down's form! Where do those shrinking layers bottom out? Well below the granularity seen by quantum mechanics, perhaps?

Son de la Loma

Posted due to the planned normalization of Cuban-American diplomatic relations announced by President Obama this week, and to celebrate the contingent release of at least a fraction of the political prisoners in Cuba (there are unfortunately many hundreds not being released).

Cuban music and American jazz have always had a lot of mutual influence, and such cross-pollination is likely to increase this century.

Doll's Eyes, Dragonflies, and the Media Gets It Wrong Again

The Washington Post reported last Wednesday on the article published in Nature on the 10th of this month, about a study of the in-flight adjustments of the dragonfly's head position while hunting. I found this a very fun-to-read article, since dragonflies are a such delight to watch in flight:

The problem is that, as we see too often in media reporting on neuroscience, the Post goes for the sensational over the truthful. Its hyperbole is that they report that dragonflies have a claivoyant accuracy in predicting their prey:

"Hunting dragonflies can perfectly predict their prey’s future movements"

But even the briefest look at the article reveals that the dragonfly is not moving its head position to keep its eyes on the prey depite its prey's movements! Instead, the predictive acrobatics of dragonfly head movement is that it can keep its eyes on the prey despite the dragonfly's own flight movements. This is akin to what is tested by a human neurologist in examination of the human "vestibulo-ocular,"or "dolls-eyes," reflex, which helps us to visually track an object even as we move in space, like a baseball fielder keeping his eye on the ball. One difference is that the article suggests that head position (and thus eye position) guides body movements in the flying dragonfly, not the reverse as in the human oculo-cephalic reflex. Says the article: "Model-driven control thus underlies the bulk of interception steering manoeuvres, while vision is used for reactions to unexpected prey movements."

It is prudent to consider that, when media reporting on topics we know about can be wrong so often, we must very often be misinformed in the subjects of which we know little, if we trust the media for such information.

By the way, this article is viewable without first paying up to pass the journal's pay-wall, a welcome sign from a venerable institution like Nature.



Sensorimotor control in vertebrates relies on internal models. When extending an arm to reach for an object, the brain uses predictive models of both limb dynamics and target properties. Whether invertebrates use such models remains unclear. Here we examine to what extent prey interception by dragonflies (Plathemis lydia), a behaviour analogous to targeted reaching, requires internal models. By simultaneously tracking the position and orientation of a dragonfly’s head and body during flight, we provide evidence that interception steering is driven by forward and inverse models of dragonfly body dynamics and by models of prey motion. Predictive rotations of the dragonfly’s head continuously track the prey’s angular position. The head–body angles established by prey tracking appear to guide systematic rotations of the dragonfly’s body to align it with the prey’s flight path. Model-driven control thus underlies the bulk of interception steering manoeuvres, while vision is used for reactions to unexpected prey movements. These findings illuminate the computational sophistication with which insects construct behaviour.

Using the Gripping Hand on the Trolley Problem: Dick Cheney, Torture, and the Way of Escape

Larry Niven and Jerry Pournelle published  a classic scifi novel 23 years ago, called The Mote in God's Eye. Recommended. The "Motie" aliens in the book have three hands, the third of which is the strongest. "On the gripping hand" means, among other connotations for the book's aliens, a third choice, which is neither horn of a dilemma.

Former US VP Dick Cheney says he'd authorize the CIA to use torture (such as water-boarding) again to prevent another terrorist attack on American citizens. This is simple "ends justify means" utilitarianism, a common CIA operative's viewpoint. Wear a black hat if it keeps more of those wearing white hats alive. Dick Cheney would switch the trolley, and he'd push the fat man on the tracks, to save multiple American citizens, it seems.

Torture in the pursuit of our enemies is not a traditional Christian ethical viewpoint, though it is a traditional Muslim one (e.g. Surah 8: Al Anfal). Though Cheney is not putting himself forward as anything other than the executive of a secular government, it still worries me that we as a nation are choosing to become more like our enemies when we fight them. What does the Christmas story say? That we choose peace and humility over arrogance and war. How can we do that and prevent further terrorist attacks? The promise in scripture is that there are ways out of our dilemmas. Said Paul, himself no stranger to dilemmas: "God is faithful, and he will not let you be tempted beyond your ability, but with the temptation he will also provide the way of escape, that you may be able to endure it."

I believe there was and is an alternative to torture in intelligence gathering. Just as, given any reasonable amount of time, there should be a third way out of the trolley problem. All that is lacking in Dick Cheney's dilemma is a bit more creativity.

Expensive Places For Christmas: New York, Paris, London, and... Hilo?

Hat Tip:

Most expensive places for holiday spending

RankCity/MetroGiftsDecorationsGreeting cardsFlowersChristmas treeCost of food4 movie ticketsBottle of wineAverage cost
1New York (Manhattan) NY$875.24$81.27$44.18$30.73$66.78$127.78$55.32$10.94$1,293.93
2Hilo HI$759.05$70.48$38.31$26.65$57.92$132.08$40.08$11.84$1,172.02
3New York (Brooklyn) NY$731.87$67.96$36.94$25.70$55.84$122.65$56.00$9.99$1,120.99
4Boston MA$746.33$69.30$37.67$26.21$56.95$111.76$46.76$9.49$1,104.88

3D Compasses in the Bat Brain

So, what is it like to be a bat? Well, for one thing, it means you have a 3D sense of direction. Useful when you wake up hanging upside down.

Arseny Finkelstein, Dori Derdikman, Alon Rubin, Jakob N. Foerster, Liora Las, & Nachum Ulanovsky
Nature (2014) doi:10.1038/nature14031
Received 25 July 2014 Accepted 04 November 2014 Published online 03 December 2014
Navigation requires a sense of direction (‘compass’), which in mammals is thought to be provided by head-direction cells, neurons that discharge when the animal’s head points to a specific azimuth. However, it remains unclear whether a three-dimensional (3D) compass exists in the brain. Here we conducted neural recordings in bats, mammals well-adapted to 3D spatial behaviours, and found head-direction cells tuned to azimuth, pitch or roll, or to conjunctive combinations of 3D angles, in both crawling and flying bats. Head-direction cells were organized along a functional–anatomical gradient in the presubiculum, transitioning from 2D to 3D representations. In inverted bats, the azimuth-tuning of neurons shifted by 180°, suggesting that 3D head direction is represented in azimuth × pitch toroidal coordinates. Consistent with our toroidal model, pitch-cell tuning was unimodal, circular, and continuous within the available 360° of pitch. Taken together, these results demonstrate a 3D head-direction mechanism in mammals, which could support navigation in 3D space.

Ahoha Friday: Puna Ku'u Aloha

While the volcanic lava flow's advance on Puna gets much of the attention, it's good to remember the good things about the district: beautiful farms and forests between the magnificent mountains and the sea.

Puna Ku`u Aloha (Puna, My Love) - by Katherine Maunakea 

`Elua mâua e Puna e
Ua `ike ia kou nani êhê
Ka `âina no ia no ku`u aloha
No ku`u aloha

Ua hui mâua me na `ohana e
Ua piha hau`oli êhê
Me ke aloha poina `ole
Ke aloha poina `ole

He nani o Mauna Kea e
Ame ka pua lehua êhê
Hanohano o Hawai`i
Hanohano Hawai`i

Puana ka inoa e Puna e
Ua `ike `ia kou nani êhê
Ka `âina no ia no ku`u aloha
No ku`u aloha

Ha`ina ia mai he `âina e
Ua nani kaulana
Me ke aloha poina `ole
Ke aloha poina `ole
Two of us at Puna
Saw your beauty
It is the land of my love
My love
We joined the family
It was filled with happiness
And unforgettable love
Unforgettable love
Beautiful is Mauna Kea
And the lehua flower
Glory of Hawai`i
Glory of Hawai`i
The theme, the name, Puna
Seen is your beauty
It is the land of my love
My love

Tell the theme of the land
Famous beauty
And unforgettable love
Unforgettable love
Source: N. Hines Collection - Composed for the Puna district in Hawai`i Translator unknown

RIP Robert Henry "Bobby" Keys, December 18, 1943 – December 2, 2014

A great blues saxophone player, but not one known for moderation in his choices. Dead of cirrhosis at age 70. Great music will be remembered.

Artificially Sweetened Soft Drinks May Increase the Risk of Stroke

This week JAMA published an epidemiological study of 451,743 Europeans from 10 countries which suggested there is an increased risk of m...