The seventh book in the Magic Tree House series is called "Sunset of the Sabertooth." This installment takes readers on another exciting journey with siblings Jack and Annie as they travel to the Ice Age. The main idea of the book revolves around the siblings' quest to save a stranded girl and return home. Their magical tree house transports them to a time where they encounter woolly mammoths, sabertooth tigers, and cave people. Throughout their adventure, Jack and Annie learn about the challenges of surviving in such a harsh environment and the importance of teamwork. The book's main message is about collaboration and helping others, even when faced with difficult circumstances.
The book's main message is about collaboration and helping others, even when faced with difficult circumstances. "Sunset of the Sabertooth" is a thrilling and educational read that keeps young readers engaged while teaching them about history and the value of empathy..
Scientists discover the secret power that makes glass frogs transparent
Some frogs found in South and Central America have the rare ability to turn on and off their nearly transparent appearance, researchers report Thursday in the journal Science.
During the day, these nocturnal frogs sleep by hanging underneath tree leaves. Their delicate, greenish transparent forms don’t cast shadows, rendering them almost invisible to birds and other predators passing overhead or underneath.
But when northern glass frogs wake up and hop around in search of insects and mates, they take on an opaque reddish-brown color.
“When they’re transparent, it’s for their safety,” said Junjie Yao, a Duke University biomedical engineer and study co-author. When they’re awake, they can actively evade predators, but when they’re sleeping and most vulnerable, “they have adapted to remain hidden.”
Using light and ultrasound imaging technology, the researchers discovered the secret: While asleep, the frogs concentrate, or “hide,” nearly 90% of their red blood cells in their liver.
Because they have transparent skin and other tissues, it’s the blood circulating through their bodies that would otherwise give them away. The frogs also shrink and pack together most of their internal organs, Yao said.
The research “beautifully explains” how “glass frogs conceal blood in the liver to maintain transparency,” said Juan Manuel Guayasamin, a frog biologist at University San Francisco of Quito, Ecuador, who was not involved in the study.
Exactly how they do this, and why it doesn’t kill them, remains a mystery. For most animals, having very little blood circulating oxygen for several hours would be deadly. And concentrating blood so tightly would result in fatal clotting. But somehow, the frogs survive.
Further research on the species could provide useful clues for the development of anti-blood clotting medications, said Carlos Taboada, a Duke University biologist and study co-author.
Only a few animals, mostly ocean dwellers, are naturally transparent, said Oxford University biologist Richard White, who was not involved in the study. “Transparency is super rare in nature, and in land animals, it’s essentially unheard of outside of the glass frog,” White said.
Those that are transparent include some fish, shrimp, jellyfish, worms and insects — none of which move large quantities of red blood through their bodies. The trick of hiding blood while sleeping appears to be unique to the frogs.
“It’s just this really amazing, dynamic form of camouflage,” said White.
Left: A glass frog in Biogeographic Chocó, Buenaventura, Colombia. Photo by Jorge GarcÍa/VW Pics/Universal Images Group via Getty Images
.
Reviews for "Unlocking Ancient Secrets: An In-Depth Look at 'Sunset of the Sabertooth"
1. Sarah - 2 stars - I found "The seventh book in the magic tree house series" to be a bit repetitive and uninspiring. The plot felt predictable and lacked the excitement and adventure that I enjoyed in the previous books in the series. Additionally, the characters didn't seem to evolve or face any significant challenges, making the story feel stagnant. I hope the next book in the series brings back the magic and thrill that initially hooked me.
2. Mark - 1 star - I was disappointed with "The seventh book in the magic tree house series." The storyline felt rushed and the writing lacked depth. The plot felt loosely connected, and at times, it was hard to follow the characters' motivations. The lack of character development made it difficult to connect with the protagonists, which was a letdown considering how well-written the previous books were. Overall, I found this installment to be a letdown and hope that the author gets back on track in the next book.
3. Emily - 2 stars - I was not impressed with "The seventh book in the magic tree house series." The story felt recycled and lacked originality. I found myself anticipating what would happen next, as it followed a similar formula to the previous books in the series. Additionally, the dialogue felt forced, and the interactions between the characters lacked depth. I believe the author could have taken a more creative approach to keep the series fresh and engaging. Overall, this book didn't live up to my expectations, and I'm hoping for improvement in the next installment.
4. Jason - 2 stars - "The seventh book in the magic tree house series" was a bit underwhelming. The plot felt disjointed and lacked a clear direction. The transitions between different scenes felt forced and often left me confused about the purpose of certain events. Additionally, the writing style seemed a bit juvenile, and I hoped for a more sophisticated tone. I think the author should have put more effort into crafting a tighter and more engaging storyline. While it had some enjoyable moments, overall, I found this book to be less enjoyable than the previous ones in the series.