Agriculture
Where Have All the Bees Gone?
Middle school science adventures
Silk’s superpowers
Amphibians
Frogs and Toads
Salamanders and Newts
Salamanders
Animals
Vampire Bats on the Run
Ant Invasions Change the Rules
A Jellyfish's Blurry View
Behavior
Sugar-pill medicine
Nice Chimps
The Snappy Lingo of Instant Messages
Birds
Penguins
Crows
Kiwis
Chemistry and Materials
Sticky Silky Feet
These gems make their own way
Picture the Smell
Computers
Getting in Touch with Touch
New twists for phantom limbs
Small but WISE
Dinosaurs and Fossils
Fingerprinting Fossils
Feathered Fossils
Have shell, will travel
E Learning Jamaica
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
2014 GSAT Results for Jamaican Kids
Results of GSAT are in schools this week
Earth
Digging into a Tsunami Disaster
Challenging the Forces of Nature
Deep History
Environment
Animal CSI or from Science Lab to Crime Lab
Plant Gas
Inspired by Nature
Finding the Past
Words of the Distant Past
If Only Bones Could Speak
Early Maya Writing
Fish
Bass
A Grim Future for Some Killer Whales
Pygmy Sharks
Food and Nutrition
Allergies: From Bee Stings to Peanuts
Food for Life
Building a Food Pyramid
GSAT English Rules
Who vs. That vs. Which
Pronouns
Order of Adjectives
GSAT Exam Preparation Jamaica
10 Common Mistakes When Preparing for the GSAT Math Test
GSAT Exam Preparation
GSAT stars reap scholarship glory
GSAT Exams Jamaica Scholarships
GSAT Practice Papers | GSAT Mathematics | Maths
GSAT Scholarship
GSAT stars reap scholarship glory
GSAT Mathematics
Math Naturals
GSAT Practice Papers | GSAT Mathematics | Maths
GSAT Mathematics Quiz, Teaching Math, teaching anxiety
Human Body
Gut Microbes and Weight
Disease Detectives
A Long Haul
Invertebrates
Flies
Daddy Long Legs
Ticks
Mammals
Labradors
Marsupials
Dolphins
Parents
Raise a Lifelong Reader by Reading Aloud
Expert report highlights the importance to parents of reading to children!
The Surprising Meaning and Benefits of Nursery Rhymes
Physics
Spin, Splat, and Scramble
Dreams of Floating in Space
Black Hole Journey
Plants
Pumping Up Poison Ivy
A Giant Flower's New Family
Nature's Alphabet
Reptiles
Gila Monsters
Copperhead Snakes
Crocodiles
Space and Astronomy
Supernovas Shed Light on Dark Energy
Unveiling Titan
A Family in Space
Technology and Engineering
Dancing with Robots
Morphing a Wing to Save Fuel
Sugar Power for Cell Phones
The Parts of Speech
What is a Preposition?
Adjectives and Adverbs
Pronouns
Transportation
Are Propellers Fin-ished?
Ready, unplug, drive
Middle school science adventures
Weather
Where rivers run uphill
In Antarctica watch the heat (and your step)
Warmest Year on Record
Add your Article

Nautiluses

Nautilus (from Greek nautilos, 'sailor') is the common name of any marine creatures of the cephalopod family Nautilidae, the sole family of the suborder Nautilina. It comprises 6 very similar species in 2 genera, the type of which is the genus Nautilus. The name chambered nautilus is also used for any species of the Nautilidae, though it more specifically refers to the species Nautilus pompilius suluensis. Living fossils: Having survived relatively unchanged during millions of years, nautiluses represent the only living members of the subclass Nautiloidea, and are often considered to be "living fossils". No suckers, many tentactles, nine teeth: The nautilus is similar in general form to other cephalopods, with a prominent head and tentacles. Nautiluses typically have more tentacles than other cephalpods, up to ninety. These tentacles are arranged into two circles and, unlike the tentacles of other cephalopods, they have no suckers, are undifferentiated and retractable. The radula is wide and distinctively has nine teeth. There are two pairs of gills. The largest adults can reach 220 mm in diameter. Pearly insides: Nautiluses are the sole cephalopods whose bony structure of the body is externalized as a shell. The animal can withdraw completely into its shell, closing the opening with a leathery hood formed from two specially folded tentacles. The shell is coiled, calcareous, mother-of-pearl-lined and pressure resistant (imploding at a depth of about 800 m). The nautilus shell is composed of 2 layers: the outer layer is a matte white, while the inner layer is a striking white with iridescence. The innermost portion of the shell is pearlescent, blue-gray. The osmena pearl, contrarily to its name, is not a pearl, but a jewelry product derived from this part of the shell. Chambers in the shell: The shell is internally divided into chambers, the chambered section being called the phragmocone. The phragmocone is divided into camerae by septa, all of which are pierced in the middle by a duct, the siphuncle. As the nautilus matures its body moves forward, sealing the camerae behind it with a new septum. The last fully open chamber, also the largest one, is used as the living chamber. The number of camerae increases from around four at the moment of hatching to thirty or more in adults. Cryptic coloring: The shell coloration also keeps the animal cryptic in the water. When seen from the top, the shell is darker in color and marked with irregular stripes, which makes it blend into the darkness of the water below. On the contrary, the underside is almost completely white, making the animal indistinguishable from brighter waters near the ocean surface. This mode of camouflage is named countershading. One of the finest natural logarithmic spiral: The nautilus shell presents one of the finest natural examples of a logarithmic spiral. (It is sometimes incorrectly claimed to be a golden spiral as well.) Jet propulsion: In order to swim, the nautilus draws water into and out of the living chamber with the hyponome, which makes use of jet propulsion. When water is inside the chamber, the siphuncle extracts salt from it and diffuses it into the blood. When water is pumped out, the animal adjusts it buoyancy with the gas contained in the chamber. Buoyancy can be controlled by the osmotical pumping of gas and fluid into or from the camerae along the siphuncles. The control of buoyancy in this manner limits the nautilus; they cannot operate under extreme hydrostatic pressures. The animal can also crawl on land or on the seabed. In the wild nautiluses usually inhabit depths of about 600-800 m, rising to around 200 m at night for feeding, mating and egg laying. Tentacle capture: Nautiluses are predators and feed mainly on shrimps, small fish and crustaceans, which are captured by the tentacles. Unlike other cephalopods, they do not have good vision; their eye structure is highly developed but lacks a solid lens. They have a simple "pinhole" lens through which water can pass. Instead of vision, the animal is thought to use olfaction as the primary sensory means during foraging, locating or identifying sexual partner. 12 month development: Nautiluses are sexually dimorphic and reproduce by laying eggs. Attached to rocks in shallow waters, the eggs take twelve months to develop before hatching out at around 30 mm long. The lifespan of nautiluses is about 20 years, which is exceptionally long for a cephalopod.

Nautiluses
Nautiluses








Designed and Powered by HBJamaica.com™