Effects of urban environments on animals

Introduction

• Recent urban developments represent massive environmental changes. It was previously thought that only a few animals were suitable for city life, e.g.
• the 31. – because of its general adaptability
• the pigeon – because walls of city buildings are similar to 32.
• In fact, many urban animals are adapting with unusual 33.

Recent research

• Emilie Snell-Rood studied small urbanised mammal specimens from museums in Minnesota.
  • She found the size of their 34. had increased.
  • She suggests this may be due to the need to locate new sources of 35. and to deal with new dangers.
• Catarina Miranda focused on the 36. of urban and rural blackbirds.
  • She found urban birds were often braver, but were afraid of situations that were 37..
• Jonathan Atwell studies how animals respond to urban environments.
  • He found that some animals respond to 38. by producing lower levels of hormones.
• Sarah Partan's team found urban squirrels use their 39. to help them communicate.

Long-term possibilities

• Species of animals may develop which are unique to cities. However, some changes may not be 40..