Lesson 7: We learned about
the asteroid impact which ended the Cretaceous Period.
Scientists divide historic time into three eras; Paleozoic, Mesozic and
Cenozic. Each era is further divided into periods. At the end of each
era and period extinct events wiped out life. The extinction events
which occurred at the end of each era were much more devastating to
existing life. After each extinction event new and different life forms were allowed
flourish.
The first major extinction event began with a complete freeze of the
Earth and happened at the beginning of the Paleozoic Era. The second mass extinction event
occurred between the Paleozoic and Mesozic Eras and was brought on by a
massive volcanic eruption in Sibera. The final mass extinction event was
caused by an asteroid impact at the end of the Mesozic Era.
Today it is widely accepted that 65 million years ago an asteroid struck our planet and wiped out most life on Earth including the dinosaurs. The video below tells the story.
Homeschooled kids often get a head start by earning college credits while still in high school. Since my oldest is 14 and very advanced in math I've spent several months researching this topic. Today many options are available for earning college credit thereby greatly reducing the cost of a college degree.
Here are three main ways to earn credit.
1.Testing
AP, CLEP and DSST are three different types of tests which can be taken and are accepted by universities. AP, or advanced placement exams are commonly offered by high schools which teach advanced classes such as calculus, English and history. CLEP exams cover many subjects typically taught during the first year of college such as American Literature, Foreign Language, Economics, Chemistry, Humanities, and Calculus. DSST exams tend to cover topics more typically gained through on the job experience such as business and computing.
Most undergraduate programs accept around one years worth of credits, or 32 credits total. They pick and choose which credits from exams they will accept. Sometimes they change their policies, and not all universities accept the same exams. That being said, passing a foreign language exam can earn potential undergraduates a whopping 12 credits. Passing most other exams result in 3 to 6 credits depending on the exam and score. Many universities like to limit the amount of credits accepted by testing to ensure students are capable of learning through more traditional classroom methods. So the bottom line is, testing can be an efficient way to skip ahead, but if the end university is known, it's best to double check with them in advance to see what credits they will accept.
2. Community College
Many undergraduate university programs will accept up to 64 transfer credits, or credits earned at another accredited institution. That means students could either take two years worth of classes at a community college, or one year of classes combined with 32 testing credits to begin an undergraduate program as a junior. Since community colleges tend to be cheaper than universities and testing cheaper than community college, this combination is an excellent way to save money on education.
Accreditation is key. There are many colleges offering classes, but not all are accredited. Again, if the university or final degree program is known, then it's best to check with that institution as to whether or not the credits earned at the community college will be accepted. If the final degree program is still being decided, checking the regional accreditation is a good idea. Here's a web link to help verify accreditation.
3. On-line College
Now that the internet has grown by leaps and bounds, many students are obtaining on-line degrees. Thomas Edison State College, Excelsior College and Charter Oaks State College are three big on-line degree institutions. What's really neat about several of the on-line programs is that students can earn a degree almost entirely through testing. They tend to accept most testing credits and even offer tests similar to course final exams which if passed, are another route for earning credit.
Students can learn at home, take AP, CLEP and DSST exams, then select an on-line school and degree program. From there, the students can study the material required by the degree program, enroll, take several tests and wind up with a degree, or enroll and take the courses on-line to complete the program.
Accredited degrees are normally accepted by universities. Therefore, if the student were to earn an on-line degree and then begin a second degree at a university, depending on the similarity of the degrees, as much as three years worth of classes could be eliminated.
Just like the numerous options for educating elementary, junior high and high school level children there are many options for college level as well. The ideal scenario would be to know the final destination university and degree program and then select a testing/community college/on-line option to feed into it. Without knowing the final goal, much progress can still be made. Just remember, each university sets its own rules. The important thing is to look for accreditation.
Check out these blog hops for more educational activity ideas.
Lesson 6: We watched videos about pterosaurs, dinosaurs and Mesozic Era sea creatures of the Triassic, Jurassic and Cretaceous periods and added Mesozic Era creatures to our timeline.
The Mesozic Era was the time of the dinosaurs. It can be broken into three time periods; Triassic, Jurassic and Cretaceous. The first flowering plants, marine reptiles, flying dinosaurs and first small dinosaurs evolved during the Triassic. During the Jurassic Pterosaurs were abundant. The Cretaceous gave rise to the first sharks, birds evolved and dinosaurs such as triceratops, and t-rex roamed the land. Mammals also made their first apearence during the Mesozic.
Miracle Planet Part 4, Extinction and Rebirth describes how volcano eruptions lead to a change in composition of the Earth's atmosphere. Among other elements, oxygen levels first rose and then fell dramatically to around 10%. The video explains how one change led to another such as the unique formation of mammal rib cages. In early species the rib cage completely surrounded the chest, but in later species, the ribs only surrounded the upper chest much like our ribs do today.
This list of videos provides a good overview of the creatures which lived during the Mesozic Era.
Largest flying Creature Ever - Pterosaurs Documentary
Scientists try to replicate pterosaur flight in this National Geographic video. Full of computer animation, this video describes different types of pterosaurs, typical pterosaur characteristics such as huge a breast bone, and landing tactics.
Dinosaurs Part 1 Extreme Survivors (Full Documentary)
Sauroposeidon were a species of long necked dinosaur which laid numerous small eggs. It's believed that the parents abandoned their babies (500 per season) and let them fend for themselves. T-Rex dinosaurs, on the other hand, are believed to have been devoted parents. This video explores different species of dinosaurs and their behavior characteristics.
Extreme Dinosaurs
Long neck dinosaurs, abounded during the Jurassic. During the Cretaceous the t-rex preyed upon creatures. It is believed that these two species didn't live at the same time. This video explores the possibility of a dinosaur even bigger than t-rex discovered in South America - giganatosaurus, living at the same time as the giant Argentinosaurus, the largest plant eater. While exploring the theory, scientists examine evidence that suggests these species of large dinosaurs may have lived in family groups.
Sea Monsters - A Prehistoric Adventure
While dinosaurs roamed the land, the seas teamed with life. This National Geographic video gives a historical fiction account of a dolichorhynchops (a pre-historic dolfin which lived during the late Cretaceous.) Following the dolichorhynchops and her brother as they journey through life, the video introduces several other sea creatures of the late Cretaceous.
After creating a basic timeline of Earth's history and learning about the wealth of life which flourished during the Paleozoic Era, we learned what brought the Paleozoic Era to its end.
The Paleozoic period of evolution was brought to a close with a mass extinction event which lasted over 100,000 years. Massive volcanic eruptions, known as flood basalt eruptions, took place in Siberia. The eruptions released sulfur dioxide gas into the atmosphere which mixed with water causing acid rain. The acid rain lead to a series of volcanic winters which caused the food system to collapse. As if that wasn't bad enough, the carbon dioxide released by the volcanoes then caused the Earth to warm. The warming resulted in altered global weather patterns. In addition, the warm air caused the ocean temperatures to rise eventually causing them to stop circulating. This created a lack of oxygen in the seas which in turn resulted in numerous creatures becoming extinct.
Catastrophe, is a video series which focuses on mass extinction events. Episode 3 focuses on the extinction which occurred at the end of the Paleozoic Era described above.
To see our earlier Evolution Unit Study Lessons please visit our Science Page.
Check out these great blogs full of educational activity ideas.
We watched several videos to learn about significant evolutionary changes which took place during the Paleozoic Era.
Time Periods in the Paleozoic Era; Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian.
Cambrian
The Cambrian Period was the first time of widespread life on Earth. While the land was barren, the seas saw an explosion of life. The single celled organisms of the Precambrian developed into multi celled creatures. At first creatures had soft bodies, but during the Cambrian Period, the first shells were developed.
Ordovician
During the Ordovician Period the warm shallow seas were filled with trilobites, sea scorpions and coral. Nautiloids evolved and after 25 million years of volcanic eruptions, the atmosphere was filled with carbon dioxide. The major evolutionary advancement of the backbone led to the evolution of the first fish.
The above video was my children's favorite as it featured Nigel, who traveled back in time to venture into the ancient seas. In addition to featuring the Ordovician Seas, Nigel explored other prehistoric environments.
Silurian
The Silurian Period gave rise to the first land based plants. The evolution of jaws was a major event as predators became much more dangerous.
Devonian
During the Devonian Period large armored fish ruled the seas and the first sharks evolved. The air was rich with oxygen, and the first creatures developed the capabilities of breathing air and walking on land. Plants which had evolved during earlier periods became numerous upon the land. Forests began to grow and the shade proved by the trees provided shelter for land animals.
The above video explores the links between prehistoric creatures in search of the first tetrapods.
Carboniferous
This was the age of giant insects as 80% of the atmosphere was filled with oxygen. The mass of trees led to the first dirt. Creatures developed the capability to produce hard shelled and amniotic eggs which led to the evolution of mammals and reptiles. Hearing developed and the relationship between carnivores and herbivores was established.
Permian
During the Permian Period mammals and reptiles continued to evolve on land.
Paleozoic Era
Overall the Paleozoic Era saw major changes in life on Earth. From single celled organisms to shells, backbones, jaws, limbs, lungs and eggs - specialization was beginning to take place. The video linked below covers the entire era.
What do you think is the coldest? Jail, Mountains or Popsicles?
In the game Apples to Apples, players select a card from their hand which they believe goes best with the selected adjective. The judge (a rotating position) selects the best match. The winner is the first person to have five of their cards selected by the judge.
Crazy combinations make this game fun. Mushy clowns, colorful throw up, and fragile spaghetti may be selected as best matches. There are several versions of this game. After becoming hooked with a novelty Jelly Belly version we purchased a version with lots more cards. The kids love this game and I like it too. It's fun, but the kids are reading (a little), learning about nouns and adjectives, and beginning to select different cards based on who is judging. After all, my daughter is much more likely to select a card that says dance or fairy and my son is more likely to select iPad. Sometimes playing to the judge really works.