The forest lemming is a small rodent the size of a mouse that lives in northern coniferous forests. This species has special genetics due to which many more females are born in populations than males.
The forest lemming differs from other lemmings and voles by an unusual sex determination system that greatly increases the number of females. It serves as important food for owls, foxes, and other predators of northern forests.
homogamy, reproduction always with fertilization, no alternation of generations
Immature form that undergoes metamorphosis before adulthood.
Whiskers count
Worker
Tail size
birth time
Dogs, dolphins, lynx hang out for 9-25 years and party on their birthday three times a year
m
Map
will celebrate their {n} birthday
g
summer mild, +15…+20 °C
t
When your next jubilee falls in {name} life years
Human
Legs count
days
How old you would be if you lived as {name}
Theoretical maximum lifespan estimated from the Dynamic Energy Budget (DEB) mathematical model. This value reflects a biological potential derived from metabolic parameters, not from direct observation — real recorded lifespans are often significantly shorter.
adult
Maturity
plants
24 to 38 grams, 10 – 25 centimeters
About health
milk
When your next birthday would fall if you lived as {name}
Repro interval
results
Eyes count
Colors
Cool summer
bark of young trees
Sex
Upcoming jubilees
Gremllins
mo
Uses an excavated underground tunnel or chamber for refuge or nesting.
alpine meadows and arctic tundra on land
Trophic type
Filters
Tail count
Palearctic realm
leaves
grass
Upcoming birthdays
Breeding structure built or used for laying eggs and raising offspring.
Winter with snow
eggs, roe or offspring develop in a nest built on the ground or close to it
Truly long lives: 40-100 years. Bowhead whales, albatrosses, giant tortoises recall their birthday at most once a year
Lifespan
nest on the ground
rains almost always, very humid
young are born live on land, not hatched from eggs or roe
bark
Age (juvenile)
Age (from birth to death)
Age (embryo)
most of Europe and Asia, various forests, steppes and tundra
Wanderers
Jubilee = every 10th birthday
Earliest developmental stage inside an egg or womb.
Business sausages
Lifespan average
nest located directly on the ground surface on land, only the mother provides parental care for the offspring
in a terrestrial nest
leaves
Incisors color
Whiskers size
grasses
live birth
What do they look like?
Maturity
emergence (insects)
end of lifespan
How do they live?
fertilization / egg laying
How do they behave?
birth / hatching
metamorphosis / end of larval stage
end of acceleration
Share
Find a pet...
Mature, fully developed individual capable of reproduction.
Pets
Lots of rain and cool summer
Legs size
{name} jubilee
Eyes size
cm
Old-timers
Find an animal or breed...
turns
Rascals
terrestrial forest
Tail color
Flooded grasslands
drink mother's milk in childhood
Litter size
mosses, liverworts and other terrestrial bryophytes
Map data sources: Ecosystem classification — IUCN Global Ecosystem Typology (Keith et al., 2022), indicative distribution maps Keith et al. (2020), https://doi.org/10.5281/zenodo.3546513; Large Marine Ecosystems — NOAA LME Program; Bathymetry — GEBCO Bathymetric Compilation Group (2026), GEBCO_2026 Grid, https://doi.org/10.5285/4f68d5c7-45eb-f999-e063-7086abc036fa; Climate data — Generated using Copernicus Climate Change Service information; Species occurrence data — GBIF.org, Derived dataset "all animals", https://zveriki.com/dataset/dataset.tsv; Terrestrial ecoregions — RESOLVE Ecoregions 2017 (Dinerstein et al., 2017), CC BY 4.0
How to care for them?
Living from 25 to 40 years. Orangutans, bald eagles, African elephants celebrate their birthday twice a year
grazing
°C
Not specified
Fur temp
alpine and arctic tundra
Where are they found?
herbivore
Whiskers color
lots of rain, cool summer, snow in winter
Feeds by cropping or nibbling low-growing vegetation or algae.
Incisors size
Legendary longevity: over 100 years. Galapagos tortoises, Greenland sharks, ocean quahogs celebrate with family once every 4 years
Offspring
Elders
leaves and stems of grasses and other herbaceous vegetation
Bro
normal sexual
Taxons
if born as {name}
age
birth date
Palearctic realm
Fur color
Close
was
Career from 7 to 15 months. Dwarf hamsters, voles, field crickets celebrate their birthday twice a month
The basics
herbivory, feed only on plant food
bark and bast of trees and shrubs
moss
My weight?
Non-stop carnival: they only live a few days. Mayflies, rotifers, midges celebrate their birthday more than twice a day
primary food sources
teeth
burrow
after transformation until death
Potential Habitat
d
In husbandry
On the go from 1.3 to 3.5 years. Forest mice, anoles, rainbow fish party on their birthday once a month
Mass
young shoots and leaves of plants
cold winter, lots of coniferous trees: spruce, pine
Mosquitoes, fruit flies, small crustaceans hustle for up to 7 months and throw a birthday party every week
Plants
Gestation
land
{name} birthday
No results found
Eyes color
On the map
Pleasant summer
all life stages
Female ♀
gnaws plants
nest located directly on the ground surface on land
Map data sources: Ecosystem classification — IUCN Global Ecosystem Typology (Keith et al., 2022), indicative distribution maps Keith et al. (2020), https://doi.org/10.5281/zenodo.3546513; Large Marine Ecosystems — NOAA LME Program; Bathymetry — GEBCO Bathymetric Compilation Group (2026), GEBCO_2026 Grid, https://doi.org/10.5285/4f68d5c7-45eb-f999-e063-7086abc036fa; Climate data — Generated using Copernicus Climate Change Service information; Species occurrence data — GBIF.org, Derived dataset "all animals", https://zveriki.com/dataset/dataset.tsv; Terrestrial ecoregions — RESOLVE Ecoregions 2017 (Dinerstein et al., 2017), CC BY 4.0
Potential habitat modelled from GBIF occurrence data. Map © Zveriki.com, licensed under CC BY 4.0.
sedges
birth year
Maturity
Skin color
terrestrial habitat, land surface outside water
sq mm
yr
comfortable summer, +20…+25 °C
How similar?
Male ♂
until the celebration
baby / chick
age as {name}
How do they breed?
On the go from 3.5 to 6 years. Hedgehogs, crows, lizards treat themselves to birthday snacks 6 times a year
Legs color
What if eaten?
Neither
from birth to adulthood
Young offspring still dependent on parental care.
nest
caring mother
What do they eat?
Where do they live?
moss
Immature individual that has not yet reached reproductive maturity.
much snow in winter, cold
early young
Hard dental structures used to bite, tear, or scrape food.
forests on land — tropical, temperate, boreal
water often floods the land, lots of grass
Duration
This is me
most of Europe and Asia, various forests, steppes and tundra
Always very wet
Gamers
How are they built?
mm
Theoretical lifespan
ml
Stars
Link copied
My age?
wk
My size?
sedge, reed and other coastal herbaceous plants
terrestrial
Taiga
Asexual
swap
Rabbits, falcons, red-eared turtles hang out for 6-9 years and party on their birthday four times a year
Where do they take shelter?
inhabit and develop on land, outside water bodies
sedge and reeds
celebrated their {n} birthday
When you would have been born if you lived as {name}
Daddies
Lifespan maximum
Hermaphrodite ⚥
Tomato
embryo
Incisors count
Length
kg
Observations
◉{N} more on tap