An Echelon Media Company
Friday December 9th, 2022

Dolphin Detail

Kids spied them first, sending shrieks aloft. Grownups grabbed their pre-lunch Proseccos and beat it down steps to join the admiring chorus. From the low bow deck of our rented sail yacht motoring (no wind) off Lanka’s south coast, we watched in noisy glee as the dolphins practised their ‘bow-riding’— surfing the wave pushed ahead and off to the side by the boat.

It looked a ton of fun and quite competitive among maybe a couple dozen bottlenoses. The big prize is to seize and hold position at wave’s apex, hurtling straight forward for a chill-and-thrill moment before some jostle or watery flux pushes left or right, forcing fall-off down the backward-flowing wake, followed by effortful struggle to maintain and improve placement among wriggling peers.

Bottlenoses frolic all around Sri Lanka, loving the continental shelf stretching out from beach to deep ocean slope. Organic nutrients flowing seaside from Lankan streams and swept in on favourable currents support a marine food chain second to none. Bottlenoses hold their breath and dive right down to the shelf floor when hungry enough for the buffet. In depths too murky for eyesight, they find their fishy prey through echolocation, akin to what bats do in the air.

Sound carries fast and far in water, with bottlenoses taking full advantage. From nasal cavities, they send rapid bursts of high-frequency clicks through a fluid, fatty ‘melon’ in their foreheads, which acts like a lens, focusing the sound into a directed beam. Echoes reverberate back from underwater features and objects, including fish. Echoed sound flows in through their lower jaws, also filled with fatty fluid, to their inner ears and thence to their brains, where wiring converts information into imagery comparable to sonogram. They see their surroundings with sound, using much the same brain matter devoted to vision in terrestrial animals. They may even use echoed clicks from their hunting partners to sharpen their ‘sight.’ They can pick out a ping-pong ball at 100 meters, roughly equal to human eyesight (verified by experiment on the lane with my son, Nate). With echolocation, bottlenoses can detect bones, muscle and organs, even fetuses, inside other creatures.

Their clicks rise in frequency as they close on their quarry, facilitating pinpoint accuracy as they strike.

Bottlenoses emerged 2-5 million years ago (mya). They fall into two recognized species: ‘common’ and ‘Indo-Pacific,’ the former inclined toward deep sea, the latter toward shore. Other distinct species may exist as well, with breaks between shore and deep sea populations prevailing widely. They belong to the Cetacean (whales and dolphins) sub-order, which originated some 50 mya in Sri Lanka’s general neighbourhood, diverging from even-toed ungulates (mammals with hooves), an order comprising present-day pigs, camels, sheep, cattle, giraffe and deer. Cetaceans claim hippos as their closest living relative. Bottlenoses fall into the odontocete branch (echolocating cetaceans with teeth), as opposed to mysticetes (filter-feeding cetaceans with baleen instead of teeth).

Tell-tale early fossils lie in the high Himalaya, lifted there as India slammed into Asia, beginning also around 50 mya and continuing since then. The earliest known cetacean, Pakicetus, was a smallish deer-like creature spending some of its time in freshwater streams that flooded seasonally. Heavy bone marrow provided ballast for ensuing forms of non-swimming freshwater waders and bottom-walkers.

By and by, of course, cetaceans learned to swim, spending more and more time chasing fish while returning to land for sleep, mating, birthing and nursing, like today’s seals and walrus. They moved downstream to deeper waters, bringing forth species adapted to diverse riverine habitats as the rising Himalaya created variegated terrain. As early as 49 mya, Ambulocetus, a slow-swimming ambush hunter sized like a sea lion, spilled into shallow seas while continuing to move ably on land, like crocodiles.

At 45 mya, Remingtonocetus improved sharply on previously-developing underwater hearing as it prowled muddy bays disfavoring eyesight. At 40 mya, some cetaceans renounced land entirely and began dispersing through global seas. Their forelimbs became flippers while their hind legs shrank into vestiges. Those who clung to land or fresh water disappeared. At around 35 mya, odontocetes split from mysticetes, beginning their deep-dive journey into echolocation. They eventually came to compete in apex predatorship with sharks dominant since when the dinosaur extinction (65 mya) swept marine reptiles into oblivion. Sometime along the way, today’s echolocating river dolphins migrated back into fresh water from the sea.

Numerous anecdotes of bottlenose intelligence require no recital here. Their brain-to-body ratio, an indicator of high intelligence, ranks among the top in the animal kingdom. Their cortical neurons may outnumber those of chimps and perhaps even rival humans. Even more fascinating is emergent science on how and why they got so brainy. As with other super-smart mammals, their story turns on social complexity, cooperativity and sensitivity. Young bottlenoses bond with and learn richly from an array of cooperating ‘aunties’ who share parental tasks, assisting actual mothers. This ‘alloparenting’ (caregiving by others than mothers) breeds emotional sensitivity among juveniles across a range of relationships, requiring and rewarding neuronal proliferation.

Meanwhile among aunties, cultivating trust relationships requires vast neuronal investment in capacities like memory, game theory, skill evaluation, situational assessment and social sanctioning. In a rare feature, females commonly live long past their reproductive years. Their long-life wisdom confers auntie benefits on juveniles and pods. That bottlenose pods fluctuate on a fission/fusion spectrum—separating and joining as circumstances vary—only intensifies pressure toward complex social judgement. Bottlenoses analyze not only how individual fellows may behave but also how different groupings may perform. Who will hunt and babysit well together under these particular conditions? Pod formation revolves largely though not exclusively around kinship. Pods coalesce around charismatic ‘socialites,’ who nurture links with other pods.

Cooperative hunting merits recognition as a bottlenose trademark. Coordinate fishing tactics include herding prey into tight balls, roundups through crescent formations, trapping against natural barriers and attack from multiple sides. In Florida, ‘driver’ bottlenoses terrify prey toward multi-dolphin ‘barriers.’ Remarkably enough, certain experts play ‘driver’ time and time again, excluding other candidates. To our knowledge, no other marine hunters anoint ‘designated drivers’ this way. Bottlenoses often assist and profit from human fishing. In Brazil they drive mullet shoals toward fishermen holding nets and eat fish that break formation.

Bottlenoses analyze not only how individual fellows may behave but also how different groupings may perform

Bottlenoses count among the few species who pass the ‘Mirror Self-Recognition’ (MSR) test. In a mirror, terrestrial mammals like chimps and orangutans can see and touch spots placed on body parts they cannot normally see (e.g. foreheads), convincingly demonstrating awareness that they are viewing their own images. Bottlenoses cannot touch spots with their flippers but they do manifest intense fascination with their mirror images. They watch themselves open their mouths, stick their tongues out, twirl, roll, blow bubbles and look at body parts. They inspect their markings closely. MSR capacity appears in species with large complex brains, high sociality and emotional empathy. Bottlenoses pass the mirror test as early as five months of age, while humans do so only at about 16 months. While this does not mean they are smarter or more empathic than humans, it does indicate high marks. They frequently offer assistance and rescue toward their own kind and toward other animals, including humans.[UH1].

Bottlenoses wield an array of whistle noises to coordinate activity, exchange information and socialize. Some experts believe this communication to be quite complex. Each individual acquires a unique ‘signature whistle’ that works as a nametag, as a locator and possibly as a signal of emotional state. Pregnant females step up their whistling as birth approaches, a behaviour called ‘fetus whispering,’ imprinting her ‘voice’ into her offspring’s memory. Intensified whistling continues for a few weeks after the birth before tapering off.

The internet lit up five years ago when a Russian scientist, no dolphin expert, claimed that bottlenoses utilize outright language, based on his whistle recordings purporting to reveal phonemes, words and sentences. Captive bottlenoses grasp at least elementary syntax, understanding the difference between ‘bring the frisbee to the ball’ and ‘bring the ball to the frisbee.’ Scepticism is in order, however. Experts on bottlenose communication quickly challenged the Russian study’s methodology and assumptions. One emerging theory of human language evolution precludes any likelihood of dolphin acquisition. Language may have emerged to facilitate transmission of toolmaking technique across generations. Language and complex manipulation draw upon much the same human brain regions as each other. No toolmaking or manipulation? No language.

Reports indicate a high incidence of illegal bottlenose hunting in Lankan waters: enforcement appears inadequate. Bottlenose meat goes to human consumption and longline fishing bait. Thriving in warm and temperate seas the world over, bottlenoses stand in no danger of extinction. If we wish them better protection, we must entertain other reasons.

Reports indicate a high incidence of illegal bottlenose hunting in Lankan waters: enforcement appears inadequate

A graduate of Harvard Law School, Mark Hager lives with his family in Pelawatte. mark.hager@gmail.com

Leave a Comment

Your email address will not be published. Required fields are marked *

Leave a Comment

Leave a Comment

Cancel reply

Your email address will not be published. Required fields are marked *

Sri Lanka shares fall on profit taking after nine sessions

ECONOMYNEXT – Sri Lanka shares slipped on Friday after gaining for nine straight sessions reverting from its highest gain in more than seven weeks on profit taking, brokers said.

“Bourse regressed to red ending the 9-day winning streak as investors resorted to book profits in blue chip counters,” First Capital Market Research said in it’s daily note.

The main All Share Price Index (ASPI) closed 0.54 percent or 47.84 points lower at 8,843.90.

The market witnessed a turnover of 1.6 billion rupees, lower than this year’s daily average turnover of 2.9 billion rupees.

The market saw a net foreign inflow of 1 million rupees. The total net foreign inflow stood at 22 billion rupees so far for this year.

The Paris Club group of creditor nations has proposed a 10-year debt moratorium on Sri Lankan debt and 15 years of debt restructuring as a formula to resolve the island nation’s prevailing currency crisis.

The government is in discussions with Asian Development Bank (ADB) and World Bank to get loans of 1.9 billion US dollars after a reform program with the International Monetary Fund is approved.

A policy loan now being discussed with the World Bank may bring around 700 million US dollars, Coomaraswamy told a business forum organized by CT CLSA Securities, a Colombo-based brokerage.

The Asian Development Bank may also give around 1.2 billion US dollars most of which will be budget support, he said.

In the last few sessions, market gained after the Central bank governor said interest rates should eventually ease despite the fears of a domestic debt restructuring as inflation falls, increased liquidity in dollar markets, and the inter-bank liquidity improves.

The more liquid index S&P SL20 closed 0.59 percent or 16.77 points lower at 2,827.72.

So far in December ASPI gained 2.2 percent.

The ASPI gained 0.5 percent in November after losing 13.4 percent in October.

It has lost 27.6 percent year-to-date after being one of the world’s best stock markets with an 80 percent return last year when large volumes of money were printed.

John Keells Holdings pulled the index down to close at 1.5 percent lower at 147 rupees.

Aitken Spence lost 2.0 percent to close at 141 rupees and Commercial Bank closed 1.4 percent down at 50.50 rupees a share. (Colombo/Dec09/2022)

 

Continue Reading

Sri Lanka bond yields end higher, kerb dollar Rs370/371

ECONOMYNEXT – Sri Lanka bonds yields ended up and the T-bills eased on active trade on Friday, dealers said.

The US dollar was 370/371 rupees in the kerb.

“The bond rates went up, however more interest was seen in the short term bills by the investors” dealers said.

A bond maturing on 01.05.2024 closed at 31.90/32.20 percent on Friday, up from 31.25/70 percent at Thursday’s close.

A bond maturing on 15.05.2026 closed at 30.30/31.30 percent steady from 30.30/31.00 percent.

The three-month T-bills closed at 30.75/31.30 percent, down from 32.00/32.25 percent.

The Central Bank’s guidance peg for interbank transactions was at 363.18 rupees against the US dollar unchanged.

Commercial banks offered dollars for telegraphic transfers between 371.78 and 372.00 for small transactions, data showed.

Buying rates are between 361.78 – 362.00 rupees. (Colombo/Dec 09/2022)

Continue Reading

Foreign minister, US ambassador discuss future assistance to crisis-hit Sri Lanka

ECONOMYNEXT — In a meeting in Colombo, Sri Lanka Foreign Minister Ali Sabry and US Ambassador to Sri Lanka Julie Chung discussed ways in which the United States can continue to support Sri Lanka going forward, the Ambassador said.

Chung tweeted Friday December 09 afternoon that the two officials had reflected on the “twists and turns” of 2022, at the meeting.

Minister Sabry was recently in Washington D.C. where he US Secretary of State Antony Blinken.

A foreign ministry statement said the two officials held productive discussions at the Department of State on December 02 on further elevating bilateral relations in diverse spheres, including the 75th anniversary of diplomatic relations which will be marked in 2023.

Incidentally, Sri Lanka also celebrates the 75th anniversary of its independence from the British in 2023, and President Ranil Wickremesinghe has given himself and all parties that represent parliament a deadline to find a permanent solution to Sri Lanka’s decades-long ethnic issue.

The US has been vocal about Sri Lanka addressing concerns about its human rights record since the end of the civil war in 2009 and was a sponsor of the latest resolution on Sri Lanka passed by the United Nations Human Rights Council. Unlike previous resolutions, this year’s iteration makes specific reference to the country’s prevailing currency crisis and calls for investigations on corruption allegations.

In the lead up to the UNHRC sessions in Geneva, Minister Sabry Sri Lanka’s government under then new president Wickremesinghe does not want any confrontation with any international partner but will oppose any anti-constitutional move forced upon the country.

On the eve of the sessions on October 06, Sabry said countries such as the United States and the United Kingdom, who led the UNHRC core group on Sri Lanka, are greatly influenced by domestic-level lobbying by pressure groups from the Sri Lankan Tamil diaspora.

These pronouncements notwithstanding, the Wickremesnghe government has been making inroads to the West as well as India and Japan, eager to obtain their assistance in seeing Sri Lanka through the ongoing crisis.

The island nation has entered into a preliminary agreement with the International Monetary Fund (IMF) for an extended fund facility of 2.9 billion dollars to be disbursed over a period of four years, subject to a successful debt restructure programme and structural reforms.

Much depends on whether or not China agrees to restructure Sri Lanka’s 7.4 billion dollar outstanding debt to the emerging superpower. Beijing’s apparent hesitance to go for a swift restructure prompted Tamil National Alliance MP Shanakiyan Rasamanickam to warn of possible “go home, China” protests in Colombo, similar to the wave of protests that forced the exit of former pro-China President Gotabaya Rajapaksa.

The TNA will be a key player in upcoming talks with the Wickremesinghe government on a solution to Sri Lanka’s ethnic issue. (Colombo/Dec09/2022)

Continue Reading