What ARE Coconuts Anyway???

On my marathon visit to the Chicago Field Museum, I geeked out most over the plant models.  There are cases and cases of gorgeous models of representative members of lots of plant families.  I, of course, amused myself by trying to guess what family was represented in each case without looking at labels.  It turns out I have forgotten quite a bit of Botany since my days at MTSU.  Time for a little refresher course.

The plant models didn't photograph well, due to the dim light, glaring glass, and lack of likely appeal of subject matter to the rest of the world.  However, I couldn't resist taking this picture of a coconut model:

Coconut model at the Field Museum.

Coconuts are completely strange to most people who live in temperate climates.  We don't tend to eat lots of them, and we rarely even see them.  If we see them, they are big brown woody balls in the produce section, or they are tiny flakes of sugary white in the baking aisle.  When we go to the beach and a real coconut washes up on shore, we don't believe people when they tell us what they are.  Well, here's your chance to stop feeling so uninformed when it comes to coconuts.

Coconuts are the fruits and seeds of the coconut palm.  A complete coconut is green or brown, oblong and bigger than a football.  The brown woody thing in the produce section is the innermost part of the fruit plus the seed of the coconut.  The whole fruit is made of layers of fibrous husk called coir.  The fruit is less dense than water, so it floats.  You may have noticed that the scratchy brown doormat outside your front door is made of coir.  Coconut palms often drop their fruit where waves can wash them into the ocean, and the fruits can then be dispersed out around the world to grow somewhere else.  The outermost two layers of the fruit are removed before whole coconuts are brought to our stores.

Field museum coconut model with labels.

Each coconut fruit contains one giant seed, which is almost entirely white with a paper thin layer of seed coat around it.  The seed contains an embryo, which can grow into a new palm, and endosperm, which is a food source for the growing embryo.  When the seed is first formed, the embryo is microscopic, and the endosperm fills up most of the space inside the seed.  The early embryo is slightly sweet and crunchy.  As the coconut starts to get larger, the endosperm becomes somewhat more gelatinous and is known as green coconut meat.  When the seeds are nearly mature, the endosperm forms solid endosperm around the outer edge of the seed and liquid endosperm inside the seed - coconut meat and coconut water.  A mature coconut seed will also contain some air, which helps it float in the ocean.  All stages of coconuts can be eaten, and they all taste coconutty, slightly sweat and delicious.  Coconuts contain a high proportion of saturated fat, unusual for a plant but much more common in butter and animal fats.

If a coconut escapes consumption by a human and floats off to a new land, it will begin to germinate.  The embryo enlarges into a root and a shoot, and it escapes the hard coconut shell through structures called eyes that look like dimples on the surface of the coconut.  As the embryo starts to grow, it forms a mass inside the coconut called a coconut apple.  The mass is soaks up the nutrients from the endosperm and transfers those nutrients to the growing shoot and root of the embryo.  The coconut apple is also edible - in fact it's considered quite delicious, though I have unfortunately not tasted it.

Writing about coconuts is definitely making me want to conduct some field research about the gastronomic virtues of the various stages of coconuts!  Anyone up for a Caribbean vacation?

Trilobites at the Chicago Field Museum

Museums can make great places for social outings, but I also love going to them alone.  I can skip the uninteresting parts and obsess as much as I want over the good parts.  On a recent trip with friends to the Field Museum a few weeks ago, the miles of enticing, juicy exhibits drove me mad with unsatisfied curiosity.  So I went back by myself and spent an entire day!

Who knew trilobites had such amazing appendages?

There was so much to see, but my absolute favorite was their collection of exquisitely articulated trilobite fossils.  Trilobites were among the earliest Arthropods, which are the jointed-appendaged animals like insects, spiders and roly-poly bugs.  They were commonly-fossilized animals from about 525 million years ago through 250 million years ago, which is an astonishingly long period of time in evolutionary history.

Trilobites are so much cuter with antennae.

I'm not sure how these fossils were separated from their surrounding rock, but their details are incredible.  Looking at these fossils, I could imagine these little critters skittering across the ocean floor and using those appendages to sense water movement and scent of prey items.

Trilobite diversity.

The exoskeleton of trilobites was thick and tough, which made it easier for fossils to form.  Scientists have been able to study the evolution of eye structures, other sense organs and delicate feeding apparatuses over time using trilobites.  There was considerable diversity of trilobite species.  It is not understood why trilobites went extinct.  Their closest living species relative alive today is probably the horseshoe crab.

A trilobite called Walliserops with what has to be a smell/taste organ on its front end.

Black Crowned Night Herons in Lincoln Park

There is a surprising diversity of animal life in Lincoln Park, and that's not even counting the zoo animals.  The latest residents of the park are what appears to be dozens to several hundred nesting black crowned night herons.    The two lumps in this picture are black crowned night herons.  Don't see lumps?  There's one in the center and one left of center near the top.  Try squinting. (Another neat thing about the picture is the lack of overlap in the adjacent tree canopies - competition for light.)

Black Crowned Night Herons Nesting in Lincoln Park

During the day, night herons sleep and nuzzle and generally take it easy.  I'd love to show you a picture of how cute this is, but the area is fenced off, and I don't have a zoom lens.  Trust me - it's cute.  Imagine fat birds cuddling with their heads tucked into each others' feathers.  Here's a better picture from the Lincoln Park Zoo website.  As the birds sleep on their nests or on nearby branches, the wind is waving the branches around like mad.  I wonder what it feels like to have wild rocking be one's version of sitting still.  It must make standing on solid ground feel uncomfortable.

These night herons are nesting in Lincoln Park for the second year in a row.  According to a birdwatcher I met by the night herons who seemed to know everything, this population used to nest in a wetland southeast of Chicago that was destroyed.  Then they moved to an island near Lincoln Park, and last year they moved here - just south of the zoo along the main promenade.  The zoo and the park have erected fencing around the nests for two years now, cutting off the main thoroughfare in the park for several weeks.  Everyone seems to be happy to welcome the birds, and they are back despite the busy park traffic, bagpipe players, dogs, soccer matches and live music concerts.  It will be interesting to see if the new habitat allows their population to survive or diminish.  They have nested earlier due to the extremely mild winter. 

Night herons hunt at night, and they eat all sorts of small meat items - fish, frogs, birds, squirrels.  Given the number of squirrels, geese and ducks in the park, it may be a good thing to have a top predator around to help control populations of these other organisms.