Dolphins on Finding Their Food:  

DolphIns keep warm because of a layer of Blubber, also called FaT, under The skIn.  In contrast, to stay warm, human beIngs have warm foods lIke gInger, blankeTs, Wood Fires, and each oTher!  InTeresTIngly, The Bones ThaT make up a DolphIn’s skeLeTon, are Filled wITh FaT and Oil, causIng TheIr bones To be boyoanT gIvIng Them an easIer Time To FLoaT.  That is so cool!   They move approxImaTely 10-15 km per hr Through The waTer. 

Range:  Eg. SpoTTed DolphIns  have A few hundred Miles / 400 km DIameTer of a Circular Range, TravelIng ~ 45 mIles / 70 km per day. (SpIlsbury; p. 9)

Their buoyant bones allow them to Stay Under waTer abouT 10 mInuTes aT a Time.  Then They surface To breaThe aIr Through TheIr blowhole, whIch has a muscular skInflap ThaT closes for when underwaTer (SpIlsbury; p.11).  Using EchoLocaTIon for finding Food, they eat SquId, KrIll, anchovIes, and mackeral, (small Fish mosTly).  It is InTeresTIng ThaT They eaT JellyFIsh wIThouT beIng harmed by Them – maybe only The small ones!  Because They have such good hearIng usIng echoLocaTIon, ThIs sense Is used more Than sIghT for FIndIng Food.  RIsso’s eaT mosTly squId.  Other River DolphIns eaT Clams, Crabs and Fish. (SpIlsbury; p. 12)  UsIng The nasal sacs found jusT behInd The BraIn, The dolphIn sends ouT sound waves called “EchoLocaTIon” ThaT surround and sIze up an objecT, fIgurIng ouT ITs generaL weIghT and sIze and shape, deTermInIng IF IT Is a Good Food Source.  (SpIlsbury; pp. 13, 14)  SpiLsbury, RIchard and LouIse; A SchooLoF DoLphIns; Illinois: 2004 HeInemann Library;  www. HeInemannLIbrary .com)  

Q – What is it that causes a Dolphin to have boyount bones?  That is, what elements cause their bones to be this way?  WHat other sea mammals have boyount bones?

]]> http://www.science-lessons.ca/dolphin-talk/feed/ 0 http://www.science-lessons.ca/oily-birds/ http://www.science-lessons.ca/oily-birds/#respond Mon, 20 Apr 2015 20:30:32 +0000 http://www.science-lessons.ca/blog/?p=1797  This Month, we are Exploring how Oil can help Birds Better Adapt to wet environments.  Charles Darwin was a naturalist in the 1800s. He studied many plants and animals and looked at how they adapted to their environments and how they changed or evolved over time. In 1831, he journeyed to the Galapagos Islands, a set of islands off the coast of South America. Here he studied how animals had to adapt to live and how they differed from one another. He was particularly fascinated with the finches and the Tortoises that inhabited each island. He noticed that the Finches on each of the islands were similar enough to each other to identify that they were related but they each had different beaks. Some also had different coloring patterns and head shapes. He further studied the vegetation available on each island and concluded that the finches had to adapt to their environments and the beak size was dependent on the types of foods and seeds that the finches ate. Some had long narrow beaks while others had short thick beaks. This was because it was easier to get nectar from fruits and flowers with thin beaks and easier to crack hard shelled seeds with thick beaks. The finches had adapted to what food source was available for them on their island! (Photo: http://upload.wikimedia.org/wikipedia/commons/thumb/d/db/Brown_Pelican,_Pelagic_Boat_Trip.jpg/750px-Brown_Pelican,_Pelagic_Boat_Trip.jpg)

Charles Darwin coined the term “Natural Selection” which means that as nature changes, the organisms that are able to adapt the quickest are the ones that get to access necessary resources and are able to survive. Organisms that are able to adapt are the ones that can continue to reproduce while those that are not able to adapt will eventually die.

Materials

3 Clear Plastic Cups

Water

Cotton Balls

Vegetable Oil

Instructions

1. Fill each cup with water.
2. Place a dry cotton ball in the water and observe what happens.
3. Dip a cotton ball in oil, making sure that half of the cotton ball remains dry.
4. Place it in a second cup and observe what occurs.
5. Place a cotton ball in oil, completely covering the entire cotton ball.
6. Place it in the third cup and observe what happens.

What’s Happening?When the cotton ball is not covered in oil, it sinks to the bottom of the cup. When it has some oil on it, the oily portion flips to avoid the water but when the cotton ball is completely covered in oil it is able to float. With Ocean Birds, they produce oil that Coats their Feathers and this allows them to float on top of the water. If they did not have this oily coating they would sink like the cotton ball did. If they only had the oily coat on the feathers that were in the water, then they may have a hard time not flipping over. By having all of their Feathers coated in oil, they are able to comfortably and safely float on top of the water until they are ready to dive under to catch fish.

Interested in how animals adapt and evolve over time? Check out these neat online resources!

• http://scienceline.ucsb.edu/getkey.php?key=427
• http://listverse.com/2013/03/25/10-weird-cases-of-incredible-animal-evolution/

And Here is one from our classroom at Science-Lessons.ca: a 52-Card Playing Deck for Ocean Learning, includes 4 several games and completely downloadable for Print and Cut-out – Crazy Starfish! Go Snorkeling! Sea Cluster! and ?Hypothesy?: Ordering:  Ocean Science: Ocean Creatures Playing Cards

Also, an updated and more improved version with Teachers Pay Teachers!