The various stages a living thing goes through during its life, these are mainly described in two ways:
In terms of years, for example, Charlie the dog is 6 months old.
In terms of life-stage, for example, Charlie the dog is an adolescent.
Both methods are found throughout the demography database and can be used to describe how proportions of individuals within populations can change through time, most commonly between years.
Lifecycle examples - species within the Demography Database:
Lifecycle of the North American Moose, Alces alces
by Danny Buss, Exeter Node
This North American Moose population is stage-structured and displayed here using 3 life stages.
The percentage of individuals in each age class varies between populations and within populations between years.
90.7% of Adults Survive over one year
On average, each adult produces 1.12 calves per year
Approximately 40% of calves survive their first year to become yearlings
100% of yearlings survive to become adults
This species is native to North America. For more information, please visit the species page here
Lifecycle of the Eurasian Badger, Meles meles
by Anna Sambrook, Exeter Node
The Eurasian Badger population commonly follows a Pyramidal Age Structure.
Social group size can vary from 1-27 individuals
The percentage of individuals in each age class varies with group size.
A greater number of Badgers are in the younger age classes as group size increases.
This is partly due to more individuals moving up an age class and reproducing.
75% of Adults aged 2 or over Survive over one year
Each adult aged 1-2 produces 0.5 cubs per year
Each adult aged 2 or over produces 1 cub per year
20% of cubs ages 0-1 survive to become aged 1-2
50% of adolescents aged 1-2 survive to become aged 2-3
This species is native to Europe. For more information, please visit the species page here (species page and ppms coming soon)
Lifecycle of the Spear Thistle, Cirsium Vulgare
by Danny Buss, Exeter Node
This Spear Thistle population is stage-structured and displayed here using 4 life stages.
31.4% of Large Rosette plants survive over one year
20.7% of Medium Rosette plants survive and remain as Medium Rosettes throughout the year
On average, each Large Rosette plant produces 187.47 seeds that do not go onto germinate in that given year
On average, each Large Rosette plant produces another 27.69 seeds that germinate and grow to become Small Rosettes
1.1% of ungerminated seeds do not germinate and remain in the seed bank for the following year
Can you complete the missing percentages using the lifecycle diagram below (click ? to reveal):
0.2 ......% of seeds that did not germinate the previous year grow to become Small Rosettes?
16 ......% of Small Rosettes survive and grow into Medium Rosettes?
11.5 ......% of Small Rosettes survive and grow into Medium Rosettes ?
43.4 ......% of Medium Rosettes survive and grow into Large Rosettes ?
This species is of the daisy genus Cirsium, native throughout most of Europe, Western Asia, and northwestern Africa. For more information, please visit the species page here
Lifecycle of the common rhododendron, Rhododendrum ponticum
by Danny Buss, Exeter Node
This Rhododendron population is stage-structured and displayed here using 4 life stages.
The percentage of individuals in each stage class varies between populations and within populations between years.
90.8% of Adults Survive over one year
68.4% of SubAdults Survive and remain as SubAdults over one year
On average, each Adult plant produces 2.445 seedlings that survive to the following year
On average, each Adult plant produces another 0.016 seedlings that survive and grow large enough to become juveniles throughout the year
22.5% of Seedlings grow to become Juvenile-sized plants throughout the year
Can you complete the missing percentages using the lifecycle diagram below (click ? to reveal):
44.45 ......% of Juveniles grow to become SubAdult-sized plants throughout the year ?
On average, each SubAdult plant produces... 1.4 ...seedlings that survive to the following year ?
19.5 ......% of SubAdults grow to become Adult plants throughout the year ?
53 ......% of Juveniles Survive and Remain as Juvenile plants over one year ?
This species is native to southern Europe and south-western Asia. For more information, please visit the species page here
Thankyou for visitng our lifecycle page. For more information on how lifecycles can be displayed in matrix format using population projecton matrices, please click here