| INCUBATED | Petrels lay 1 egg which is ___ for about 60 days |
| GENEALOGY | Lay one egg cracked in direct descent |
| YELLOW | Chicken or egg, which came first in that lowly dispute? (6) |
| WORSE | "Which is ___...?" |
| FELDSPAR | Rock-forming mineral consisting of aluminium silicates accounting for about 60 per cent of the earth's crust by weight |
| MOTHER | Cubs stay with their ___ for about 18 Months |
| PARENTS | Baby foxes stay with their ___ for about 7 months. |
| NEST | Where 38-Across lay 1-Across ... or a word hidden in 20-, 27-, 44- and 51-Across |
| OVIPAROUS | Description of any creature which reproduces by laying eggs which are hatched outside the body (9) |
| EMU | Large bird that lays green eggs, which are incubated by the male |
| OSTRICH | It is the largest of all birds alive today. It stands 2.5 m tall and weighs about 130 kg, more than twice as much as the average human. It cannot fly, but it is a very fast runner, at about 60 km/h. |
| EMPEROR | The male of this type of regal-looking penguin incubates his mate's eggs for 60 days, eating nothing and losing as much as 45% of his body weight. The chick spends the first two months of its life on |
| JAIL | Where US volunteers spend 60 Days In, on C4 (4) |
| OIL | Petrels produce a stomach ___ which is made up of wax esters and triglycerides that is stored and used as an energy rich food source for the adults during their long flights |
| GUILLEMOT | This bird is the largest of the "auks" at about 45 cm long and 1 kg in weight. The female of this species lays her one egg on the ground, where both parents share incubation duties. They can dive in w |
| OEUF | "Why do the French have only one egg for breakfast? Because one egg is an ___" (old joke) |
| STAGGERING | One egg standing up in line, which is amazing (10) |
| NOCURE | "There is ___ for birth and death... ": Santayana |
| NOTABLE | "The new building is ___ for its unusual design" |
| PREGNANT | A mother wolf is ___ for a short two months |
