All posts by Jon Buchheim

People say spiders are scary, but I am glad I don’t have crinoids hiding all over my house.

Liparometra regalis - Crinoidia - Feather Stars
Liparometra regalis Crinoidia – Feather Stars

Liparometra regalisCrinoidia Feather Stars

Etymology
regalis – Latin = ‘of or pertaining to a king’
Crinoidea – Greek from krinon – ‘a lily’

Crynoid Facts:

  • They’re not plants – Despite their resemblance to flowers, are not plants. They are echinoderms – animals characterized by their rough, spiny surface and 5 fold symmetry.
  • They’re not starfish – They are related to starfish in that they are both echinoids. Like starfish, Crinoids usually have 5 fold symmetry.
  • They eat with their arms – They are filter feeder and they wave their feathery arms which are covered with a sticky mucus to capture food -floating detritus. The feathery arms have growths called pinnules. The pinnules have rows of tube feet on each side of a groove running down the center. The tube feet that cover the arms pass the food to the center where it is put into their mouth.
  • Crinoids are old… really really old – They have been around since the Ordovician period – 490 million years ago. Paleontologists however, think they could be even older than that.
  • You’re more likely to find a crinoid fossil than you are living crinoid – Crinoids today are relatively rare however they were once plentiful and diverse. These echinoderms were at their height during the Paleozoic era (544 to 245 million years ago ). They could be found all over the world, creating forests on the floor of the shallow seas of this time period. There were so many in places, that thick limestone beds were formed almost entirely from their body parts piled on top of each other.

Why would anyone get excited about T. rex, when you have crinoids !

Robert Bakker – paleontologist

Won’t have to wait to tell your grandchildren about.

Linckia multifora
Linckia multifora

Multipore Sea StarLinckia muitifora
Interestingly the Multipore exhibits autotomy (self amputation) and often sheds one or more arms. In this process, the arms become detached at various positions and each can grow into a new individual. This happens with such frequency that it is considered to be a means of asexual reproduction. Few individuals are found that do not exhibit some evidence of prior autotomy. Individuals always lose their largest arm to autotomy. From the “tail” of the comet, the arm that was dropped off, 4 arms are slowly growing back to form a new complete sea star. As the process continues, the little arms grow bigger, and they will eventually end up looking like stars again. It appears that most of the populations can be made up of these comet individuals. The sexual (gonochoric) produced embryos hatch into planktonic larvae spending up to two years in this stage before settleing and metamorphose into pentamorous juveniles which develop into young sea stars with stubby arms.

In a study on Hawaii, it was found that the detachment of an arm is not caused by a sudden snap. Most fractures take place about 1 inch from the disk. A small crack appears on the lower surface which spreads to adjacent parts, then the tube feet on the arm and the body pull the two parts of the animal in opposite directions. The event may take about one hour to complete. The damaged tissues take about 10 days to heal and the animal grows a new arm over the course of several months. The detached arm is known as a “comet” and moves about independently. It takes about 10 months to regenerate a new disk with arms 0.5 inch in length.

Sea stars can probably undergo asexual reproduction more easily than other animals because they have most of their organs repeated in each of their arms. Also, they don’t have a centralized nervous system, it would probably be a trickier thing to do if they also had to regenerate a full brain. Because of the position of their mouth, it is also one of the first thing to be regrown, so they don’t have to starve for too long before they can feed again. If many species of sea stars can regrow a missing arm, only a few can, like Linckia multifora, regrow a full animal from just an arm.

Etymology
Linclda – The genus is named after the German naturalist Johann Heinrich Linck
muitifora multi– ‘much or many’ and +fora = ‘forum’?

Halley’s Comet is arguably the most famous comet. It is a “periodic” comet and returns to Earth’s vicinity about every 75 years, making it possible for a human to see it twice in his or her lifetime. The last time it was here was in 1986, and it is projected to return in 2061.

Whale flight

Humpback Feeding
Humpback Feeding

Humpback whale feeding on herring. It scientific name is Megaptera and literally means mega wings.

Etymology
Humpback – is derived from the curving of their backs when diving.
Megaptera –  Greek mega– “giant” + ptera ‘wing’ refers to their large front flippers.
novaeangliae – French = “New Englander” and was probably given by Brisson due to regular sightings of humpbacks off the coast of New England.

Like a kite string in the sky

Tropicbird
Tropicbird

White-Tailed TropicbirdPhaethon lepturus

  • Tail Streamers are white and can be up to seventeen inches long.
  • Forages by plunging into water from flight, submerging briefly; sometimes by swooping down to surface without striking water, taking flying fish in the air.
  • May feed most actively in early morning and late afternoon.
  • Courtship displays include two birds flying gracefully in unison, one above the other, with higher bird bending tail down to touch tail of lower bird.

Etymology
Phaethon – Greek mythology- son of Helios; killed when trying to drive his father’s chariot and came too close to earth
epturus: Greek leptós = ‘slender, thin’, and +ourá = ‘tail’

Songs and Calls:

A piping “keck-keck-keck

Horns, Horns on my head…

Manta Horns
Manta horns

The distinctive ‘horns’ on either side of its broad head are actually derived from the pectoral fins. During embryonic development, part of the pectoral fin breaks away and moves forward, surround the mouth. The way the horns develop is surprisingly simple. All it takes is a tiny notch that deepens and widens as the manta grows, separating each fin into two distinct parts: one for feeding and the remainder for swimming. This give the manta ray the distinction of being the only jawed vertebrate to have novel limbs. These flexible horns are used to direct plankton into its mouth.

Oh, give me a horn on the sides of my head
Where I keep them rolled up all tight;
And where the food is just right I reach out to bite
And the plankton is funneled precisely in.
Chorus
Horns Horns on my head…

Jon B – from Home on the Range

Lt. Ellen Ripley’s least favorite fish.

Angelfish Mouth
Angelfish Mouth

Due to an extra joint in their jaw design, Angelfish can protrude their upper and lower jaw out away from their had and then bite really hard, something other fish can not do.

A big angelfish can extend its jaws a couple of inches. They can reach into nooks and crannies on the reef. They are powerful biters. They can yank.

Oh and yes, the title is an homage of the movie Alien

Nautical Mile Fact

Nautical_Mile
Nautical Mile

A Nautical mile is based on the circumference of the earth, and is equal to one minute of latitude (1/60th of a degree). It is slightly more than a statute mile (1 nautical mile = 1.1508 statute miles.) Nautical miles are used for charting and navigating.

Side note:
Degrees of latitude are parallel so the distance between each degree remains almost constant but since degrees of longitude are farthest apart at the equator and converge at the poles, their distance varies greatly.

Each degree of latitude is approximately 69 miles (111 kilometers) apart. The range varies (due to the earth’s slightly ellipsoid shape) from 68.703 miles (110.567 km) at the equator to 69.407 (111.699 km) at the poles. This is convenient because each minute (1/60th of a degree) is approximately one nautical mile.

A degree of longitude is widest at the equator at 69.172 miles (111.321) and gradually shrinks to zero at the poles.