Transcript STUDY THE PICTURE and TITLE – what do you predict will be

The Colors of Ancient Sea Reptiles
Discovered
STUDY THE PICTURE and TITLE
– what do you predict will be
explained in this article?
Answer here (2-3 sentences):
(1) Leatherback turtles, and other ancient sea reptiles, had black skin. That’s the
conclusion of a new study on three fossilized sea reptiles, in which scientists
reconstructed the color of the creatures’ skin by detecting traces of the pigment
melanin. The melanin may have been an adaptation for living in cold water and
for camouflaging the animals. Colors of ancient animals are usually impossible
to tell—skin cannot be preserved over millions and millions of years. Color
usually remains a mystery.
(2) Thanks to technology and a little luck, scientist Johan Lindgren and his team
have found a solution, revealing reptile colors from as far back as 190 million
years ago.
“On rare occasions, the fossil record reveals examples of exceptional
preservation,” Lindgren wrote.
(3) The researchers found that dark smudges on three fossils—an ichthyosaur,
a mosasaur, and an ancient leatherback turtle—were examples of such
exceptional preservation, possibly the remains of skin tissue.
(4) To see if the smudges truly represented reptile skin or were simply bacteria
covering the fossils, Lindgren’s team scraped it off with a scalpel and examined
its atomic structure. They determined that the tissue contained mostly melanin.
(5) Lindgren’s team concluded that the three reptiles all sported a similar shade
of brown/black due to the melanin in their skin. Cool. Why is that significant?
For one, the dark color could have provided camouflage in the murky depths
where the reptiles lurked.
(6) Perhaps more importantly, melanin allows animals to heat themselves faster
and to maintain higher body temperature because it absorbs a large amount of
sunlight and heat. Think of a drab box turtle basking on a rock at high noon.
High melanin content allows them to go into colder water.
(7) Mosasaurs are the stuff of sci-fi imaginations run amok, 60-foot shark eaters
that lived around 85 million years ago. Ichthyosaurs were smaller and fishlike,
living 100 million years earlier, and the leatherback turtle in the study lived
around 55 million years ago.
(8) In other words, these beasts evolved similar colors even though they lived
millions of years apart.
1. Summarize the story in 2-3 sentences:
A:
2. UNDERLINE three main ideas in
the article.
3. What are the two reasons the animals
would need melanin and dark skin in the
underwater environment?
A:
4. Skin is almost never is found on fossils.
What parts of an organism do you think
make good fossils?
A:
Paleo Dieters Beware — Cavemen
Had Cavities Too
STUDY THE PICTURE and TITLE
– what do you predict will be
explained in this article?
Answer here (2-3 sentences):
(1) A new study finds that prehistoric humans had as many cavities as modern
people. Had they existed, we’re betting four out of five Pleistocene dentists
would have recommended chewing fewer nuts and acorns.
(2) Tooth cavities in humans have long been associated with eating
carbohydrate (sugar) -rich foods. Here’s how it happens: Bits of the
carbohydrates get stuck on teeth, creating a happy environment for
bacteria, which produce acids that cause tooth decay. Researchers had
thought that cavities were tied to the beginning of agriculture and farming,
when humans began eating more grains and processing their food more
than earlier humans had.
(3) New research suggests, however, that cavities and other forms of oral
disease have been a pain in the mouth for our species for much longer. The
rate of cavities in teeth from North African hunter-gatherers more than
14,000 years old was close to that of modern industrialized populations
chomping on doughnuts and gulping sugary sodas.
(4) Researchers focused on a place in Morocco called Grotte des Pigeons
because of its combination of both multiple human burials and middens.
The middens are basically trash heaps full of plant and animal material.
More than half of adult teeth studied from the site had cavities.
(5) Researchers mostly found Holm oak acorns and Maritime pine nuts as the
main edible nuts at this site, though wild oats, pulses and pistachio nuts
were also found. Researchers concluded that acorns and pine nuts were a
important foods of these hunter-gatherer people.
(6) Acorns and pine nuts, as well as pulses and oats, are high in carbohydrates.
Eating them created the perfect environment for decay-causing bacteria in
the mouths of the hunter-gatherers. Land snails were another diet staple for
the population, and researchers theorized that gritty particles in the snails
may have increased tooth wear and accelerated cavity development.
Still, the high rate of cavities came as a surprise to researchers.
1. Summarize the story in 2-3 sentences:
A:
UNDERLINE 2-3 important/ main ideas
2. Knowing about unicellular organisms
is important to understand this article.
UNDERLINE a section of the story that is
an example of this, THEN explain why it is
important:
A:
3. Why were scientists SURPRISED that
ancient people had cavities in their teeth
like modern humans?
A:
UNDERLINE a section of the article that
supports your answer.
Which article do you think is more relevant to what we are
studying in class currently and explain WHY.
Article #1 or #2?
Explain why(2-3 sentences):
Cite a piece of evidence from either article that supports
your answer to the above question:
Write it here
WHY does this example support your answer?
Answer: