Thursday 25 October 2012

Water.

It’s the deceptively simple questions that always trip you up.

It rained yesterday. I would have been happy to explain the water cycle or re-answer Beans’ question on the composition of clouds for the fourteenth time (water not fluff – she remains unconvinced) or even take a stab at how plants use the water. At 7:45am what I was unprepared to answer was Bunny’s question.

What is water made of?

It started off okay – I know what water is made of. It’s made of hydrogen and oxygen. Two hydrogen atoms and an oxygen atom. H2O. She knows what oxygen is. She does not know what hydrogen is or what an atom is or why two things in air hook up and become liquid. Or how they find each other. Or how they stick together. I used to know. At 7:45am on a Tuesday morning I do not know.

I have one rule I made for myself when answering questions from the girls. Never make something up. Admit you don’t know and then find out together.  

So here’s what we found. I am hoping it will help the next parent whose kid isn’t satisfied with “H2O” as an answer.

A single drop of water has millions of water molecules in it. Water molecules each have one oxygen atom (red) and two hydrogen atoms (white) connected by covalent bonds. Covalent just means they share electrons to stick together. Hydrogen atoms are positively charged and oxygen atoms are negatively charged when stuck together (dipole).


I think it’s kinda cute. I mean slap some googly eyes on that guy and it could happily star in a morning cartoon.

But then how do they stick together to make water? That would be hydrogen bonding. When lots of water molecules hang out together the electrical attraction from the charges make them get really close together, making them hard to get apart which raises the boiling point and makes it a liquid at room temperature. They are also constantly breaking apart and sticking back together, which give water some of its more unique qualities.


Water molecules stickin’ together. Bunny and I think the water molecules look like cartoon frog heads.

Here we are enjoying the properties of hydrogen bonding on our vacation:


Some cool water things to know:

  • Water is 11.1% hydrogen and 88.9% oxygen by mass even though there are two hydrogens. This is because hydrogens are way smaller atoms than oxygens.
  • Water is the only natural thing on earth that can be in all three states: liquid, solid and gas.
  • The water that is on earth now is made up of the same exact elements that made the water on the planet when dinosaurs were here.
  • Trees are two thirds water. So is your brain.

PHEW! Well, now we will all have a big glass of hydrogen covalently bonded with oxygen. I’m going to put a tea bag in mine.

References:

Thursday 18 October 2012

Honk if you love geese

This post has a soundtrack!



So it seems the intro to my last post brought up some questions about geese. Good ol’ Branta canadensis. A true Canadian icon or a true Canadian pest… I guess it depends on how you feel about goose poop.

But no one can deny that the Canada Goose migration is iconic and a clear sign of fall. And it’s hard not to notice, what with all that honking and all. The CAGO (that’s its nickname in the birding world – all birds have a four letter code) has its distinctive V formation and coupled with their need to communicate during flight (click here to hear them!) and you have a sight that often stops us in our tracks to stare upwards. The wing-whooshing as they pass over is pretty cool too.

The geese are headed to the southern US, much like my in-laws, and can travel more than a 1000km a day, also much like my in-laws (family groups with goslings take longer to get there though, probably because they have to stop and pee a lot.) However I’m pretty sure my in-laws don’t feel the need to honk at things the whole way. At least I hope they don’t.

So why do the geese?

Simply, communication. They need to tell each other where to stop, changes in speed, direction – they are simply keeping everyone updated of the plans. Geese are one of the most vocal species out there - starting even before hatch. Research has shown about 13 different calls – ranging from “hey there” to “holy crap run!” to “this grass is seriously awesome, no seriously, try this patch here.” (Yes, I make up voices for birds when I’m watching them). No one wants to be the guy who took the wrong turn in Mississippi and missed the cornfield party. The V-shape is linked to communication too – everyone can see everyone, sound travels easily and changes are done quickly.

And you know that weird taking turns being the leader thing that cyclists do? (It always confuses me – you are leading, why are you letting the other guy just go ahead? It’s a RACE!) Anyway, they didn’t invent that – geese have been doing it for years. Scientists (aren’t they awesome) think that the V creates a drafting effect where the geese in behind take advantage of the air currents. Plus the geese aren’t racing, so taking turns on the hard job makes sense, unlike cyclists (seriously, you are racing guys).

Honk!

For anyone who wants more goose information here’s a link to another Canadian icon – Hinterland Who’s Who. http://www.hww.ca/en/species/birds/canada-goose.html

Dooo doo doo doo doo doooooo. 


Monday 8 October 2012

The Birds.



We have a few different games to play in the car. A particular favourite is called Canada Flag Ahoy. It’s a complicated game where if you see a Canadian flag you have to yell “Canada Flag Ahoy” at the top of your lungs before your sister does. But driving also offers the opportunity to stare out the window and take in some of the things you wouldn’t necessarily notice and ask a bajillion questions about them in the five minute drive to school. It’s fall here now so we’ve talked about why leaves change, why the geese need to yell while flying, where all the butterflies went and if they will they see the geese when they get there. 

The girls have noticed a lot of species are on the move south this time of year, including their grandparents, and we’ve been talking a lot about which species stay, which go and how they get to where they are going. This brings me to my real topic. 

Bird Shows.

Some species gather in large numbers around this time of year to prepare for migration. I have spent a number Augusts and Septembers with a VHF receiver driving the shorelines of Lake Erie listening for my tagged Black Terns within in the hundreds staging. I’ve inspected hundreds of Great Egret legs standing on mudflats looking for the little red bands we’d put on a couple hundred kilometers away.  Birds do some significant travelling this time of year and even birds know a road trip is more fun with a buddy, or a couple of thousand buddies.

What we usually see here on our way to school are robins, blackbirds and starlings. They are putting on some impressive displays rivalling the snowbirds at the air show (and sometimes just as loud). There’s a few old trees out behind our place that are a favourite roosting spot, so luckily we get to witness quite a few bird shows. I’m sure you’ve all seen the large flocks seemingly moving as one unit, changing direction and then all suddenly landing. In late summer a number of species join flocks, they fly together, feed together, roost together and migrate together. These staging flocks can be tens of thousands of birds (although not that many fit on the trees in our neighbourhood). Nobody quite knows yet all of the hows or whys, but that doesn't make it any less stunning. 

A video of this phenomenon in starlings (as a bonus it's a nice wetland restoration story too):




And just to make this post extra awesome - did you know that the larger flocks actually show up on weather radar? And that since the discovery that the strange ghosting patterns that kept showing up on screens were actually birds migrating it’s been tracked (thank you fellow science nerds).  Now even the air force uses it to avoid collisions! Bunny was thrilled to know that you can track insects too and is planning to watch for her beloved butterflies to return in the spring (OK – it’s not that good, you can just see swarms, but we’ll pretend they are butterflies). Now instead of trying to describe all this I will let some of the ridiculously cool images speak for themselves:

Dispersal at Sunset:

Roost rings as the flocks depart:


More information and pictures here: http://www.virtual.clemson.edu/groups/birdrad/ (which is where the above images are from) 

I wonder if they play games on the way down. We should teach them Canada Flag Ahoy.