Unit five

I. Pre-reading Activities.

A. Practise the pronunciation of the following words and memorize them.

• ancient /ˈeɪntʃənt/

• gracile /ˈgræsɪl/

• Southern Utah /ˈsʌðən ˈjutə/

• Tanzania  /ˌtænzəˈnɪə/

• Cretaceous Period /krɪˈteɪʃəs ˈpɪərɪəd /

• creature /ˈkriːtʃə/

• Mesozoic Era /ˌmiːsəˈzəuɪk ˈɪərə/

• Gondwana /gɔnˈdwɑːnə/

• associate /əˈsəusieɪt/

• initially /ɪˈnɪʃ(ə)li/

• carnivore /ˈkɑːnɪvɔː/

• dinosaur /ˈdaɪnəsɔː/

B. Read and discuss the questions.

→ Have you ever thought about researches made on crockies?

→ What do you know about these friendly creatures?

→ Would you dare research crocodiles?

→ Could you guess the meaning of “heavily plated tails”? Explain it in your own words.

→ Do you know who was the crocodile “hunter” Steve Irvin and what is he famous for? Share your knowledge about his research with your friends in class.

C. Match the following words with their definitions.

1. fossils A. the inner surface of the hand from the wrist to the base of the fingers

2. row B. to cover the body with strong protective covering

3. armor (v.) C. the remains (or an impression) of a plant or animal that existed in a

past geological age and that has been excavated from the soil

4. carnivore D. something shown or examined as an example; a typical example

5. floodplain E.  one of the large teeth at the back of the mouth in humans and some other animals used for crushing and chewing food

6. specimen F. a line of things, people, animals, etc. arranged next to each other

7. crisscross G. a part of something, especially a large part

8. molar H.  to pass back and forth through or over 

9. palm I.  level land that may be submerged by floodwaters

10. chunk J. an animal that eats meat

II. Reading Activities.

1. Read the text below using a dictionary. Mammal-like crocodile fossil found in East Africa, scientists report

Ohio University-led study uncovers skeleton of unusual Cretaceous creature

Andrea Gibson.

ATHENS, Ohio - Fossils of an ancient crocodile with mammal-like teeth have been discovered in the Rukwa Rift Basin of Tanzania, scientists report in this week’s issue of the journal Nature. The unusual creature is changing the picture of animal life at 100 million years ago in what is now sub-Saharan Africa.

“If you only looked at the teeth, you wouldn’t think this was a crocodile. You would wonder what kind of strange mammal or mammal-like reptile it is,” said study lead author Patrick O’Connor, associate professor of anatomy in the Ohio University College of Osteopathic Medicine.

The scientists describe the new species of notosuchian crocodyliform as a small animal — “its head would fit in the palm of your hand,” O’Connor said — that wasn’t as heavily armored as other crocodiles, except along the tail. Other aspects of its anatomy suggest it was a land-dwelling creature that likely feasted on insects and other small animals to survive. 

O’Connor and his international research team, funded by the U.S. National Science Foundation and the National Geographic Society, found a complete specimen of the crocodile in 2008, and now have recovered portions of seven different individuals in southwestern Tanzania. The tooth row with molar-like teeth initially puzzled many experts. Other ancient and living crocodiles typically boast relatively simple, conical teeth that serve to seize and tear prey; they swallow flesh in large chunks. 

The molar teeth of the new species, named Pakasuchus (Paka is the Ki-Swahili name for cat and souchos is Greek for crocodile), possessed shearing edges for processing food, similar in form to the teeth of some mammalian carnivores. “Once we were able to get a close look at the teeth, we knew we had something new and very exciting,” O’Connor said. 

The research team’s discovery that the animals had heavily plated tails but relatively unarmored bodies with gracile limbs suggests that the creatures were quite mobile. They probably actively foraged on land, unlike water-dwelling crocodiles.

The new species isn’t a close relative of modern crocodilians, but is a member of a very successful side branch of the crocodyliform lineage that lived during the Mesozoic Era, O’Connor said. 

While the specimens of the newly discovered animal and its close relatives are unusual, the study suggests that the creatures were abundant during the middle Cretaceous, from around 110 million until 80 million years ago. 

“The more exploration we do, the more we push the boundaries on what we thought we knew about animal life on the planet,” O’Connor noted.

Based on other fossils discovered as part of the Rukwa Rift Basin Project, Pakasuchus lived alongside large, plant-eating sauropod and predatory theropod dinosaurs, other types of crocodiles, turtles and various kinds of fishes. 

“We suspect that notosuchians were very successful in the southern hemisphere because they were exploiting a certain ecological niche, one in which they were able to successfully compete with other small-bodied, terrestrial animals,” O’Connor said. “This is an environment that was quite different from what we typically think of for crocodiles.” 

Little is known about the vegetation during this time period, but detailed sedimentological analysis of the Rukwa Rift Basin shows that “the landscape was dominated by a large, long-lived river system with multiple, crisscrossing channels and low-relief vegetated floodplains in between that apparently supported a relatively rich vertebrate fauna,” said Eric Roberts, an assistant professor of geology at James Cook University who collaborated on the research while at Southern Utah University.

During much of the Cretaceous Period, Afro-Arabia, India, Madagascar, Antarctica, Australia and South America were joined together as the southern supercontinent Gondwana. Relatively few Cretaceous-age mammals have been recovered from this part of the world, and most of those discovered don’t appear to be related to modern mammals. Notosuchian crocodyliforms may have taken up residence in a “mammalian niche” in Gondwana during the Cretaceous Period.

“One of the reasons we’re working in different parts of the southern hemisphere, including Africa and Antarctica, is that not as much exploration has been done in these locales. We are still piecing together the puzzle of what animal life was like in these places,” O’Connor said. “Perhaps we just haven’t found the mammals yet.”

B. Look through the text again and translate the following parts from English into Russian:

― If you only looked at the teeth, you wouldn’t think this was a crocodile.

― You would wonder what kind of strange mammal or mammal-like reptile it is,” said study lead author Patrick O’Connor, associate professor of anatomy in the Ohio University College of Osteopathic Medicine.

― new species of notosuchian crocodyliform

― its head would fit in the palm of your hand

― that wasn’t as heavily armored as other crocodiles

― it was a land-dwelling creature that likely feasted on insects and other small animals to survive

― The tooth row with molar-like teeth initially puzzled many experts.

― “Once we were able to get a close look at the teeth, we knew we had something new and very exciting,” O’Connor said. 

― Relatively few Cretaceous-age mammals have been recovered from this part of the world, and most of those discovered don’t appear to be related to modern mammals.

― we are still piecing together the puzzle

C. Read the text again and answer the following questions.

1. When and where did crocodiles originate according to the reading?

2. What is the most important discovery of the research discussed in the text?

3. Where have Cretaceous-age mammals been recovered?

4. What can you say about the environment crocodiles lived in according to the scientists?

5. Could you give a precise description of an ancient crocodile?

6. How can discoveries of fossil species that combine peculiarities of different classes and orders be helpful for modern science? 7. What unusual traits of notosuchian crocodyliform can you describe? 8. Why is it interesting for scientists to work in the southern hemisphere?

D. The text below has been jumbled. Arrange the paragraphs in the correct order to make a full story.

Crocodile Tears! Crocs, Caimans, and Gators Really Do "Cry" - But Not for Sentimental Reasons!

(1) Because they live in salty environments, crocodilians must rid their bodies of excess salt. Crocodiles and gharials have modified salivary glands on their tongue that are used to excrete the excess salt. Although alligators and caimans have the same glands, the glands are non-functional.  All crocodilians, however, also use their tear glands to help rid their bodies of excess salt. This excretion resembles very salty tears - thus, the expression, "Crocodile Tears." The expression tends to mean "crying without much real emotion involved."

(2) As representatives of the largest reptiles on earth and in much the same way as the "other" large four-legged reptiles - the monitor lizards - they resemble so much the dinosaurs of old with their huge sizes, their ferocious appetites, and their imposing presence in their natural habitats.  However, they are now also threatened with human interactions (retribution for attacks on livestock and persons and development taking over their habitats) and impending habitat loss due to climate change and global warming.

(3) The American continents are the only places where crocodiles and alligators live in the same habitats.

(4) The crocodiles, caimans, gharials, and alligators - in the crocodilia order of large reptiles of which there are 23 recorded species in three families (Crocodylidae, Alligatoridae, and Gavialidae) - live in mostly salt or brackish water in the tropical regions of the world.