Tuesday, March 28

Past and present leviathans of land and sea


A reconstruction of Patagotitan mayorum. — Illustration by Mariolanzas/Wikimedia Commons

AS the new calendar year dawns, we often reminisce on yesteryears with happy memories of dear family and friends’ gatherings and especially those who have departed this life, as well as wondering what the New Year 2023 has in store for us.

It was a mere 58 years ago when, as a first-year student at Oxford University, I visited the university museum to be astounded by the skeleton of a massive dinosaur in the main hall. I cannot for the life of me remember which of many dinosaur species it was. In my generation, dinosaurs were past entities, so unlike the better educated children of today even at primary school level.

My two very young grandsons and a grandson of a friend in Kuching can identify models of dinosaurs with their accurate names. Today, in modern parlance, the word ‘dinosaur’ has come to mean an aged, successful, wealthy entrepreneur, businessman, or politician. Because of my age, many of my former students may regard me as a dinosaur but I was a firm but fair headmaster and am far from wealthy! Once real dinosaurs ruled our planet but came to a disastrous end yet, many of our present large animals have inherited their characteristics.

What factors contributed to the demise of dinosaurs?

It was at the end of the Cretaceous period (145 to 66 million years ago) that saw the mass extinction of dinosaurs. The precise nature of a catastrophic event is still debated. It is possible that massive volcanic eruptions blackening out the sky thus causing climate changes or perhaps asteroid invasions of our planet may have caused huge fires. The most likely theory is related to a huge asteroid hitting the present location of the Yucatan Peninsula, Mexico, creating a massive blast and heatwave, throwing vast amounts up into the atmosphere. Soot particles were expelled upwards, blocking sunlight and thus impacting plant growth, creating massive tsunamis and flooding inland areas.


Titanosaur skeleton cast on display at the Field Museum of Natural History in Chicago. — Photo by Zissoudisctrucker/Wikimedia Commons

As from March 2023, a replica skeleton of one of the four titanosaur species, Patagotitan mayorum, is to be displayed at the Natural History Museum, London. It will be 12 metres longer than that of the Blue Whale skeleton currently on display there. The resin cast of this monster was accidentally discovered in 2008 by an agricultural worker, who picked up its thigh bone. Palaeontologists have since excavated the site in the desert about 250km west of Trelew at La Flecha.

This titanosaurus lived about 101 million years ago in the early Cretaceous period and its bones are those of a young adult with a calculated height of 37 metres and a weight of approximately 57 tonnes (equivalent to that of nine and a half African elephants). Because of its very long neck and bodily weight, it has a very long tail to maintain its balance. With such a long neck and as a herbivore, they could easily gather leaves from trees, gobbling them up at a fast rate only to be fermented in their huge stomachs thus producing vast amounts of methane and adding to global warming at that point in geological time.

These creatures laid eggs about 15cm in diameter and upon hatching baby titanosaurs emerged growing up to 37 metres in length! These findings suggest that they lived in a once forested region of Patagonia which now, because of sudden climate change in the past, has become semi-desert.

It is anticipated that this massive skeleton will encourage museum visitors to think about our present and most vulnerable species of animals, which are now facing not dissimilar battles for survival albeit it of an anthropogenetic origin.

Forward to the present: today’s gigantic ocean whale

The largest creature ever known to exist is the Blue whale (Balaenoptera musculus) with a length of nearly 30 metres and weighing almost 200 tonnes, almost the weight of 30 African elephants. There are four species located in the following oceans: (i) North Atlantic and North Pacific, (ii) the Southern, (iii) the Indian and South Pacific, and (iv) the Northern Indian. It is likely that a fifth species will be recognised from the waters off the coast of Chile.

Shape and diet

With its ’U’ shaped head, slender body, long flippers and a small dorsal fin near to its large tail, its upper jaw is lined with between 70 to 395 baleen plates (horny plates growing from its palate). With two blowholes, it can expel water nine to 12 metres high in the air. From the surface, its skin is a mottled greyish blue in colour but at depth it is blue.

These leviathans can live for up to 90 years and feed almost exclusively on krill. They devour krill by lunge feeding, swimming towards the krill at high speeds and engulfing 220 metric tons of water at any one time. They then filter the krill by using their baleen plates to squeeze out the water before digesting about 1,000kg of krill per day. They migrate between summer feeding pastures of krill near the poles and their winter breeding grounds near the tropics.


AFP file photo shows the enormous tale of a blue whale.

Blue whales reach sexual maturity at between eight and 10 years of age and are polygamous species of animal, mating during the autumn months. The female’s gestation period is between 10 and 12 months with calves born at a live weight of two to three metric tons and a length of six to seven metres. Breeding at an average rate of 2.5 years between births, reproduction rates are slow. Their calves consume up to 4kg of their mother’s milk each day.

Threats to these gigantic creatures of the deep

The main natural threat to the Blue Whale is the Orca Whale, especially in attacking the calves. Until the end of the 19th century, Blue Whales were abundant in all our oceans but from then on, they have been hunted, for their blubber and meat, by commercial whalers almost to the point of extinction.

In 1966, the International Whaling Commission banned all Blue Whale hunting, but ‘rogue’ whaling countries still operate. This species face dangers from ship propellor strikes, oceanic pollution, ocean noise (often submarine and ship echo sounders) and climate change, which is altering their feeding grounds. Many a stranded and disorientated Blue Whale is discovered on beaches worldwide.

Today’s total Blue Whale population is estimated at between 10,000 and 25,000 individuals. These whales are classified as ‘Endangered’ on the IUCN Red List.

On Christmas Day 2022, two young boys of my family and an Australian youngster of a friend’s family took great pleasure in wearing their light blue baseball caps, as presents from an aged Father Christmas, emblazoned with a message on each which simply said, ‘Save Our Whales’! Perhaps, we can all contribute in 2023, in our own ways, to secure the future of wildlife on our only Earth.

Why do affluent nations contribute so much of their peoples hard earned incomes, in their exchequers, to promote lunar exploration when wildlife and, indeed, human life, is perishing in the only world we know? I leave that thought for readers to eschew. May 2023 be a better year for all animals, birds, and fish, and us humans too.