Surely there are some things that I know for certain, aren’t there?  Maybe not!  Here are a few “facts” that have not stood up to the test of time.

  • Trees grow in the daytime when they can use the sun to photosynthesize carbohydrates from carbon dioxide, right?

    Majestic Tree
    Image by RegalShave from Pixabay

Not according to the latest research from the Swiss Federal Institute for Forest.  Their studies show that trees actually do most growing at night.  They monitored seven common species for up to eight years.  Simply stated, what they learned was that air humidity was the key to tree growth.  During the day, when the air becomes drier, trees temporarily lose more water through transpiration than they absorb through their roots.  As a result, growth stops, regardless of photosynthesis.  

(As a reminder: The same amount of water vapor results in higher humidity in cooler air than warm air.)

  • If an animal is decapitated, it’s dead, right?

Not if we are talking about the sea slug (Elysia marginata).  Separate the head from the body and both sections can continue to live independently of the other for several weeks to a few months.  Eventually, the headless body will start to decay.  However, the head will regrow a new body, heart, and other organs.  

These Elysia marginatas are not the only organisms that can perform this magic.  At least one other slug species can do something similar. 

  • The Chesapeake Bay was formed when glaciers carved the channels and troughs a the end of the last Ice Age, right?
Chesapeake Bay
Image by mcfisher from Pixabay

That’s only part of the story.  Around 35 million years ago, a bolide (a very bright meteor) exploded near where the Bay sits today, creating a deep canyon.  The subsequent tsunami continued to redefine the area. The displaced water reached all the way to the Blue Ridge Mountains.  

The impact’s effect was only confirmed in 1993.   Oddly, it was missed when the Chesapeake Bay Tunnel was built because the excavation didn’t go deep enough to reveal the evidence.

Thanks to @DrAndrewThaler for the tweet that clued me in to this information.  

I can’t wait to find out what new information will dispel the next set of facts!

Sources: 

More about tree growth at night — https://www.wsl.ch/en/news/2021/06/why-trees-grow-at-night.html

More about beheaded slugs — https://www.newscientist.com/article/2270397-some-sea-slugs-behead-themselves-and-then-regrow-their-bodies/

 For more information about Chesapeake Bay formation — https://www.nps.gov/chba/learn/geological-formation.htm

No doubt you are aware that Iceland is currently experiencing an active volcanic eruption.   Fagradalsfjall is located near the capital of Reykjavik.

You can see live lava flow here:  https://youtu.be/BA-9QzIcr3c

What is flowing right now from that volcano is believed to be “primary magma.”  That is the direct melting of the earth’s mantle.  The mantle is that layer that lies between the crust and the inner, mostly iron core.  Not every volcano spews primary magma.  For scientists who study this stuff, also known as igneous petrologists, this is an exciting development.

Fagradalsfjall is a shield volcano with a tuya.  First, let’s explain the shield description.  This means that the volcano is wide with gently sloping sides.  Lava can travel far in this environment.  The tuya describes a steep-sloped area where lava has erupted through a glacier or ice flow.  Lots of dynamic things can happen when so much fire meets so much ice.  The tuya is the rarest form of volcano.

Mount Etna, in Sicily, is also erupting. This one began with Strombolian eruptions and ash emissions.  Strombolian eruptions are relatively mild to moderate bursts of incandescent clots of lava or lava bombs.  Mount Etna is also a composite volcano (sometimes called a stratovolcano) which means it has steep sides and a conical shape comprised of layers of ash and lava.

Kīlauea is another shield volcano.  It is the youngest and most active volcano on the Big Island of Hawaii.  It has been erupting almost non-stop since 1983.  

Popocatepetl, in central Mexico, is a composite volcano. Where Kilauea is young, this one has been around since the Pleistocene era.  That was at least 11,700 years ago.  The Aztecs gave the volcano its name which means the “smoking mountain.”  By the way, more than 20 million people live close enough to this volcano to be impacted by a major eruption.    

Today, there are 28 volcanoes in active eruption and more than 50 additional sites registering seismic unrest or minor activity.  The earth is constantly in renewal. 

For more information, check out these sources:

What erupting today — https://www.volcanodiscovery.com/home.html

More about tuyas — https://www.sciencedirect.com/science/article/pii/S027737911400002X

Facts and photos — https://earthobservatory.nasa.gov