Archive for the ‘Marine animals’ category

Talking Dolphins

July 25, 2013

While it is self-evident that God designed humans in His image, and gave us the responsibility to manage His creation (Genesis 1:26-28), it is also obvious He created other creatures with quite a bit of intelligence, too. Dolphins are a great example, and researchers are learning more about their ability to communicate with each other, even responding when their “signature whistle” is replayed to them. A recent Wall Street Journal article discusses recent research findings, and includes an audio clip of dolphins responding when their “name” is replayed back to them. Below are some video clips my family shot recently in Port Aransas, TX. Dolphins are very curious, and occasionally will come right up to the boat. In the video, you can see the dolphins, hear them echolocate (rapid clicking sounds) and communicate with each other (whistles). Some of them have also learned to wait patiently near fishermen, and when an undersized fish is caught and released, they pounce on it! They also like to “hitch a ride” at the bow of moving boats.

When around wild dolphins, remember that they are, well, wild, and they have teeth! Try to enjoy them from a distance (federal law says 50 yards), but if they come up to you, don’t gun the motor and race away from them, because you might hit one and injure it. Instead, just enjoy them! If you are swimming or wadefishing and they approach, just relax and be observant. They are curious yet cautious, which is how we should be, too.

Spotted Dolphin

May 21, 2012

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The Atlantic spotted dolphin (Stenella frontalis) is one of about 40 species currently classified in the family Delphinidae.

A spotted dolphin comes in for a close look at my camera.

Reaching lengths of 8 feet, spotted dolphins are usually smaller than Atlantic bottlenose dolphins, and tend to travel in bigger groups, or pods, of 20 or more. Like most dolphins, spotted dolphins are very family-oriented, which brings up an interesting question. Because they normally tend to stick together as a family, dolphin pods are by nature reproductively isolated. And most biologists consider reproductive isolation to be the most important factor in contributing to diversification over time. But why are there only about 40 classified species of dolphins? Some say dolphins have been around for tens of millions of years, which seems like plenty of time to have more than 40 species develop on our watery planet.

Besides reproductive isolation, dolphins are classified as different species based on traits that humans consider different enough to distinguish one population from another. But compare the 40 or so “species” of dolphins to the 150-plus “breeds” of dogs currently registered by the American Kennel Club. All breeds of dogs are considered to be one “species”, Canis familiaris, all developed over the last 2000+ years. However, just like a laborador retriever can successfully breed with a golden retriever, so too a spotted dolphin can successfully breed with the Atlantic bottlenose dolphin. Yet we classify them as different species, placing spotted dolphins in genus Stenella and bottlenose in genus Tursiops!

The truth is, a lot of confusion exists regarding how to define a species. Much confusion is remedied though, when we think of dolphins as one big family, or baramin. “Baramin” is the Hebrew word for “kind”, and is used many times in Scripture to describe God’s creative acts.  Scripture is clear that their are different kinds of things, and that “all flesh is not the same flesh” (I Corinthians 15:39). Also, as Peter Leithart explains, the “The Bible unveils a God who gives enough and more than enough”, and we see this attribute revealed in His creation, too. We see one family of dolphins, which God gave “enough and more than enough” to adapt and diversify over time.

So few dolphin species, so little time

And speaking of time, that brings me back to the question of “why only 40 dolphin species?” With their natural tendency towards reproductive isolation, one might think that if the earth were as old as some say, we wouldn’t have dozens, we would have hundreds of dolphin species. I believe the fact that we don’t see much diversity is good evidence that the best interpretation of earth age is the one that lines up with the genealogies recorded in Scripture. It is not-so-common knowledge that research reveals both the genetic and geneaological trends in humans point to thousands, not millions or billions of years of earth history. It certainly seems the dolphin baramin displays a similar trend.

Dolphins, oil and gas, and Christian stewardship

Here are some video clips from a May 2012 trip into the Gulf of Mexico, about 30 miles SE of Freeport, TX.

I want you to consider everything you see in the video, not just the dolphins. Included are video clips of a pod of about 18-20 spotted dolphins.  But you’ll also see a clip showing massive schools of fishes surrounding an oil and gas production platform. Think about it; what you are seeing is a man-made structure that also serves as an artificial reef, providing food and shelter for giant schools of snapper, blue runners, etc. And the spotted dolphins have come to reap the fishy harvest! Some conclusions I hope you will draw are 1) the dolphins are better off because of man’s activities in the Gulf, 2) the fish are better off because of man’s activities in the Gulf, and 3) Humans are better off because of man’s activities in the Gulf!

So, the next time you hear about the “evils of oil and gas”, or the “endangered marine mammals”, or “humans are destroying the planet”, remember this video! Followed properly, God’s dominion mandate for Christians in Genesis 1:26-28 will make our planet a more productive place, not just for mankind, but for all kinds. Only a fool would destroy the planet, but only a fool would overprotect it, too. God gave us an entire planet and then some to use, so let’s use it wisely!

Do you have a question or comment? Please post it below.

Bottlenose Dolphin

November 10, 2010

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Bottlenose Dolphins (Tursiops truncatus)are a common sight along the Gulf Coast. These images are from Port Aransas, Texas. The photo below was used on the cover of the October 1, 2009 edition of the Port Aransas “South Jetty” weekly newspaper:

Copyright 2009, David E. Shormann

Adult dolphins reach lengths up to 12 feet (4 meters), and males are normally larger than females. Dolphins typically live 20-30 years, but have been known to live up to 50 years. Bottlenose are dark gray on top, fading to white or pink underneath. An average sized (550 lb) dolphin will eat 20-50 pounds of fish each day! Dolphins find fish to eat using sight, but they can also hunt at night and in murky water by using echolocation. When a dolphin uses echolocation, it is basically creating a picture of its environment using sound. Although dolphins produce a range of sounds, the most useful sounds for echolocation appear to be clicks of short duration released in single pulses or trains of pulses. These clicks may be repeated up to 800 times per second. Dolphins have no vocal chords, so the sounds they produce are believed to be created by forcing air through their nasal passages and nasal sacs. The bulbous head of the bottlenose is filled with fatty tissue, and is believed to act like a lens, concentrating the clicks into a “beam” of sound. Their sounds can travel over half a mile, and they can even use their sounds to stun prey. So not to confuse outgoing sounds with returning sounds, outside sounds enter through the lower jaw and travel through the skull by bone conduction. Fat and oil bodies within the lower jaw vibrate, adn the sound is channeled directly to the middle ear. The hearing center in a dolphin’s brain is well-developed, probably so that it can analyze and interpret returning sound messages. For comparison, a human ear can hear in the range of 16 to 20,000 vibrations per second. A bottlenose dolphin responds to frequencies above 150,000 vibrations per second!

A dolphin’s vision is not as good as human’s, and it is believed they have no sense of smell, but they can taste. Dolphins reproduce sexually, and like all mammals, give birth to a baby that feeds on its mother’s milk. Dolphins have an 11-month gestation period, with babies being born mainly in the spring. Dolphins swim in groups or pods of related dolphins, and work together to trap fish, squid, and other food items.

Sometimes dolphins like to jump in the bow wake of large ships, like these three dolphins are doing:

Copyright 2009, David E. Shormann

Sometimes they jump for no apparent reason!

Copyright 2009, David E. Shormann

Here is a video of dolphins jumping in the bow wake of a tanker:

While the dolphins in these photos and video are jumping, they also like to dive, and have been recorded to dive to depths of about 1,000 feet (300 m)! They have a horizontally-positioned caudal fin, which they move up and down for propulsion. This is different than in fishes, which move their vertically-positioned tails from side to side. A rigid dorsal fin and a pair of flippers are used for stability and turning. Dolphin’s skin is smooth and slippery, allowing them to attain speeds up to 25 miles per hour (16 kph).

Dolphins rank second in intelligence only to us humans, but even as smart as they are, their creative abilities are less than toddler’s. Only humans, who were created in God’s image, were designed to be anywhwere near as creative as Him. You won’t see dolphins building skyscrapers, composing music, or drawing self-portraits! Dolphins are capable of learning many things though, and are easy to train in a way that shows off their incredible strength and agility, as shown in this video from the Texas State Aquarium:

The Marine Mammal Protection Act forbids harassing, feeding, or interfering with a dolphin’s normal activities. Sometimes, their “normal” activities include being extremely curious and approaching humans within just a few feet.

Copyright 2009, David E. Shormann

If you visit the Gulf Coast, you may not be greeted by a dolphin in such a personal way, but if you are, turn the boat motor off, keep out of the water (dolphins may bite), and enjoy the show!

Click on this link to print a COLORING PAGE:       bottlenose dolphin