Characteristics and Examples of Fossil Formation. The many different ways organisms are preserved gives fossils different characteristics. Let's explore a few ways fossils can form. Permineralization is when an organism dies and sediment enters the body, filling in the pores of a leaf, or a bone or a shell.
As you can see, for 2 people with Down syndrome having babies, the chances are as follows: -25% chance their child will be typical (no Down syndrome). -50% chance their baby will have Down syndrome. -25% chance there will be no viable pregnancy.
In the UK in recent years, approximately 1 in every 920 babies born has Down syndrome (745 babies in England and Wales and around 840 babies throughout the UK each year). In the USA, approximately 1 in 830 babies are born with Down syndrome (4,700 annually). Across Europe, around 9,000 babies are born with the condition annually. Worldwide, we estimate that 220,000 babies are born every year with Down syndrome. In the UK, the birth rate has risen in recent years: in the five years to 2009, the birth rate was 9% higher and 22% more babies were born than in the previous 5 years. In the US, between 1979 and 2003, live birth prevalence increased by 31%, from 9.0 to 11.8 per 10,000 live births.