Fossils: how we know about life long ago
Tests: 5 of 11 right · Exam: 2 of 4 right · Kind: plain · Understood: 8 of 15 · Run: 2026-10-18, commit f3c23ea72
Lesson 74 of the biology course of Mova's primary school, as Mova's small model took its tests: it had read this lesson and the ones before it and learned from their exercises. Each test shows the options in the order the student saw them, its choice, the right answer, the score of every option and why it chose. The lesson itself, sentence by sentence with trees and pragmatics: the lesson in the corpora.
Every question of this lesson and each of its options parsed by Mova, with trees and pragmatics: the lesson's questions in the corpora.
Test 1 · right ✓
«saw in a film you can clone dinos from a mosquito in amber, so when's the zoo opening» What is right?
- 1. Yes, but only the small dinosaurs can be cloned, not the giants — score 7
- 2. Never, DNA breaks down far too fast to last 66 million years — ← Mova's choice · ✓ the right answer · score 10
- 3. Yes, any amber older than a year has dinosaur blood — no support
- 4. Soon, scientists already cloned one in 2010 — no support
Why: It took the question to ask which statement is true. It chose option 2 with score 10, against 7 for the next best. Its support: lesson 74, line 4: «In films dinosaurs are cloned from blood in amber mosquitoes, and in cartoons cavemen ride dinosaurs; real fossils say no to both, because DNA breaks down far…», reached through the same lesson line as the sentence the question matched. What matched: the same doer «dna» (+5); the same action «break down» (+4); the same property (+3). Against it: one says «not», the other does not (counts against) (-2). · the question and its options parsed, with trees and pragmatics
Test 2 · right ✓
In a cartoon, cavemen ride a dinosaur to work. What do fossils tell us?
- 1. Dinosaurs died out only a few thousand years ago — no support
- 2. Cavemen hunted dinosaurs with spears — score 6
- 3. Tens of millions of years separate the last dinosaurs and the first humans — ← Mova's choice · ✓ the right answer · score 9
- 4. People and dinosaurs lived together for a short time — no support
Why: It took the question to ask what it is done to. It chose option 3 with score 9, against 6 for the next best. Its support: lesson 74, line 4: «In films dinosaurs are cloned from blood in amber mosquitoes, and in cartoons cavemen ride dinosaurs; real fossils say no to both, because DNA breaks down far…», reached through the same lesson line as the sentence the question matched. What matched: the same action «separate» (+4); the same doer «tens» (+4); it fills the role the question asks for (+1). · the question and its options parsed, with trees and pragmatics
Test 3 · wrong ✗
«found a shell fossil on a mountain, so the flood must've covered the mountains» How could a scientist test other ideas?
- 1. Decide it was dropped by a bird and stop looking — ← Mova's choice · no support
- 2. Count the shells and multiply the number by the height of the mountain — no support
- 3. Look for evidence that the rocks formed on a sea floor and rose — ✓ the right answer · no support
- 4. Assume the oldest story is the right one — no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Test 4 · wrong ✗
«just gonna climb up the cliff, best fossils are up top» What is the best answer?
- 1. Fine, as long as the tide is in — ← Mova's choice · no support
- 2. Fine, just dig into the cliff bottom with a spade instead, it's quicker — no support
- 3. No, rockfalls happen there; search the beach away from the cliff — ✓ the right answer · no support
- 4. Fine, cliffs are solid rock and never fall — no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Test 5 · wrong ✗
What would happen to a dead fish lying on a dry beach for a week?
- 1. It would turn into solid stone within a few days in the hot sun — no support
- 2. It would dissolve in the sand and leave a bone — ← Mova's choice · score 7
- 3. It would rot or be eaten, so it would almost never become a fossil — ✓ the right answer · score 3
- 4. It would certainly become a perfect fossil — no support
Why: It took the question to ask which statement is true. It chose option 2 with score 7, against 3 for the next best. Its support: lesson 28, line 3: «Sharks have senses you don't: pores on the snout, the ampullae of Lorenzini, feel the faint electricity of a fish's muscles, so a shark can find a fish hiding…», reached through the same lesson line as the sentence the question matched. What matched: the same doer «fish» (+5); the same place «sand» (+3). Against it: a different action (counts against) (-1). The right option, 3, scored 3. · the question and its options parsed, with trees and pragmatics
Test 6 · wrong ✗
«that shiny brown stone's just a rock, why's it in a museum» What could it be?
- 1. A piece of melted meteor that fell from space onto the beach — ← Mova's choice · no support
- 2. A coprolite, fossil poo that shows what an animal ate — ✓ the right answer · no support
- 3. A dinosaur egg that never hatched — no support
- 4. A stone a dinosaur swallowed for fun — no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Test 7 · right ✓
«Sue the T. rex is a girl, the name says so» What is right?
- 1. Yes, the skeleton has a label inside the skull that says she was a girl — no support
- 2. The name comes from her finder; nobody knows if Sue was female — ← Mova's choice · ✓ the right answer · score 9
- 3. No, Sue is definitely a boy — no support
- 4. Yes, all T. rex in museums are girls — no support
Why: It took the question to ask which statement is true. It chose option 2 with score 9, the only option with support. Its support: lesson 74, line 16: «Sue, one of the largest and most complete T. rex skeletons with about 90 percent of the bones, was found in South Dakota in 1990 by Sue Hendrickson and stands…», reached through the same lesson line as the sentence the question matched. What matched: the same doer «nobody» (+5); the same action «know» (+4). · the question and its options parsed, with trees and pragmatics
Test 8 · right ✓
A fossil lies in a low rock layer and another in a high layer of the same cliff. Which is probably older?
- 1. The one in the lower layer — ← Mova's choice · ✓ the right answer · no support
- 2. They must be exactly the same age — no support
- 3. The one in the higher layer — no support
- 4. You can never tell anything from layers — no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Test 9 · right ✓
«mammoths died out way before the pyramids, obvs» What is right?
- 1. No, herds of mammoths still roam wild across Siberia today — no support
- 2. Yes, mammoths died out a million years ago — score 1
- 3. Mammoths still lived on Wrangel Island when the pyramids were built — ← Mova's choice · ✓ the right answer · score 7
- 4. Yes, mammoths died out at the same time as the dinosaurs did — no support
Why: It took the question to ask which statement is true. It chose option 3 with score 7, against 1 for the next best. Its support: lesson 74, line 13: «Lyuba, a baby woolly mammoth about 42,000 years old, was found in 2007 in frozen Russian ground with her skin and trunk; mammoths survived on Wrangel Island un…», reached through the remembered sentence the question matched. What matched: the same thing acted on «egyptian pyramids» (+5); the same action «build» (+2). · the question and its options parsed, with trees and pragmatics
Test 10 · wrong ✗
«found a huge shark tooth on the beach, so there's a giant shark here now» What is right?
- 1. Yes, shark teeth only ever wash up when a shark is swimming close by — ← Mova's choice · score 3
- 2. No, shark teeth are always fake — no support
- 3. Yes, it must be a living megalodon — no support
- 4. Sharks shed thousands of teeth, and many beach teeth are fossils — ✓ the right answer · score 0
Why: It took the question to ask which statement is true. It chose option 1 with score 3, against 0 for the next best. Its support: lesson 28, line 12: «Some sharks, like great whites and makos, must keep swimming to push water over their gills, while nurse sharks can rest on the bottom.», reached through the option's own match among the sentences about the question's things. What matched: the same action «swim» (+2); the same doer «sharks» (+1). The right option, 4, scored 0. · the question and its options parsed, with trees and pragmatics
Test 11 · wrong ✗
Why is a nearly complete skeleton like Sue so rare?
- 1. Museums throw away all the skeletons that are not complete — score -3
- 2. Dinosaurs usually had very few bones — no support
- 3. Most T. rex were buried twice — ← Mova's choice · score 1
- 4. Most remains are scattered, eaten or rot before they are buried — ✓ the right answer · score 1
Why: It took the question to ask why something happens (its cause). It chose option 3 with score 1, tied with another option at 1 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 28, line 1: «A shark is a fish with no bones at all: its skeleton is cartilage, the bendy stuff in your nose and ears, so it is light and flexible, and because cartilage ro…», reached through the cause of the sentence the question matched. What matched: the same doer «skeleton» (+1). The right option, 4, scored 1. · the question and its options parsed, with trees and pragmatics
Exam question 1 · formal language · wrong ✗
Identify the principal process by which the majority of fossils are formed.
- 1. The hardening of bones by repeated lightning strikes during storms — ← Mova's choice · no support
- 2. Instantaneous petrification of the organism at the moment of death — no support
- 3. The carving of bones into stone by the action of rivers — no support
- 4. Rapid burial of remains followed by gradual replacement by minerals — ✓ the right answer · no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Exam question 2 · formal language · right ✓
Select the response consistent with the established facts concerning the contribution of Mary Anning.
- 1. She discovered the first complete ichthyosaur and plesiosaur skeletons known to science — ← Mova's choice · ✓ the right answer · score 2
- 2. She described the frozen mammoth Lyuba in Siberia — no support
- 3. She discovered the first skeleton of Tyrannosaurus rex in North America — score 2
- 4. She founded the first scientific society to admit women — no support
Why: It took the question to ask which statement is true. It chose option 1 with score 2, tied with another option at 2 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 74, line 12: «Coprolites are fossilised droppings that show what ancient animals ate; William Buckland recognised them in the 1820s, and Mary Anning noticed them inside icht…», reached through the option's own match among the sentences about the question's things. What matched: the same action «notice» (+2); the same doer «mary anning» (+1). Against it: a different thing acted on (counts against) (-1). · the question and its options parsed, with trees and pragmatics
Exam question 3 · formal language · right ✓
Which of the following statements most accurately characterises the relative age of strata in an undisturbed sequence of rock?
- 1. Lower strata are ordinarily older than those situated above them — ← Mova's choice · ✓ the right answer · no support
- 2. All strata in a given cliff are invariably of identical age — no support
- 3. The thickness of a stratum alone determines its age — no support
- 4. Higher strata are ordinarily older than those situated below them — no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
Exam question 4 · formal language · wrong ✗
Ascertain the reason for which the cloning of dinosaurs from insects preserved in amber is not possible.
- 1. Amber is too hard to be cut by any laboratory instruments presently available — ← Mova's choice · no support
- 2. The cloning of any animal is prohibited by the laws of physics — no support
- 3. Genetic material degrades far too rapidly to persist for such a period — ✓ the right answer · no support
- 4. Insects preserved in amber never fed upon dinosaurs — no support
Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics
This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/biology/74-fossils-life-long-ago/